What is ONVIF?

Relation matrix and HD-SDI HD

Simulation application of surveillance cameras and the development of new observation

Basic knowledge of surveillance cameras

Monitor camera principle

High-definition network camera technology development trend

The three core problems in the development of HD monitor

Analysis of high definition IP camera market

How to choose a suitable lens installed surveillance

HD-SDI Camera

What is the difference between DVR, NVR and IPVS?


What is ONVIF?

In 2008 May, by the axis (AXIS) combined with Bosch (BOSCH) and Sony (SONY) three announced that will work together to set up an international open network video products standard network interface development forum, named ONVIF (Open Network Video Interface Forum), and to the public, the principles of openness jointly formulate open industry standard. Is an open network video interface forum. As of 2011 March, already had 279 companies to join the ONVIF membership. In 2008 November, the forum officially released the first version of ONVIF specification. In 2010 November, the forum has released version second of the ONVIF specification. The device discovery, real-time audio and video camera, PTZ control, video control, video analysis etc.. ONVIF standard function The ONVIF specification describes the network video model, interface, data type and data interactive mode. And reuse some existing standards, such as the WS series of standards ONVIF’s goal is to realize a video network framework, network video products produced by different manufacturers (including video front-end, video equipment etc.) complete interoperability. Realization of ONVIF standard Defined by the ONVIF specification of equipment management and control part of the interface are provided in the form of WebServices. The ONVIF specification covers the definition of XML and WSDL complete. Each support ONVIF standard terminal equipment shall be provided with the function of the corresponding Web Service. The client server and data exchange using SOAP protocol. ONVIF in the other parts such as audio and video stream through the RTP/RTSP. The advantage of ONVIF specification Synergy: different manufacturers to provide products, can be through a unified “language” to communicate. To facilitate system integration. Flexibility: the end user and the user need not be bound by the inherent some equipment solutions. Greatly reduced the development cost. Guarantee of quality: the continued expansion of the specification will be guided by the market, follow the norms also satisfy the mainstream user demand. The future of ONVIF Due to the adoption of the WSDL+XML model, the expansion will not make ONVIF specification had too much trouble. Convenient expansibility and XML strong and SOAP protocol development will attract more people to pay attention to and use ONVIF code. The ONVIF organization is getting more and more powerful, and with the field of PSIA, compared to HDCCTV, occupy the absolute advantage of personnel. The member enterprise equipment manufacturers and integrators famous at home and abroad. A set of specification, protocol of the life cycle, and market share are closely related. And the development of the ONVIF specification is oriented by market, by the user to enrich. Each member enterprises have to strengthen, expand the ONVIF specification right. Covered by ONVIF standard field will continue to increase. At present, relevant content access control system will be incorporated into the ONVIF specification. In the rapid development of security, monitoring system today, the efficiency and quality of the leading value brought by it is self-evident. The ONVIF protocol provides such potential. The realization mechanism of standard ONVIF Web Service introduction WebService is a modular component of the network, based on distributed, to perform a specific task. WebService mainly uses HTTP and SOAP protocol data transmission in Web. Web users can use SOAP and HTTP to call remote objects by calling the Web method. The client based on WSDL description document, will generate a SOAP request, the request may be embedded in an HTTP POST request, sent to the Web Services Web server. Web Services request processor parses the received SOAP request, call the corresponding Web Services. And then generate the corresponding SOAP response. Web server SOAP response, then pass through HTTP response way to send messages back to the client. WSDL is a Webservices description language (Web Service Description Language) abbreviation. Used to describe a Web service and how to communicate with the Web service of the XML language, provides detailed instructions for the user interface. Construction of SOAP message SOAP Simple Object Access Protocol abbreviation. Is a protocol based on XML. A SOAP message is a simple XML document, contains the following elements: The Envelope element must, to this XML document is identified as a SOAP message The optional Header element, contains header information The Body element contains all necessary, call and response information The optional Fault element, provide the relevant information in the error handling the message In sends to the Web Service SOAP request, field in the Body element should be consistent with the WSDL data type. In the process of constructing SOAP, must be obtained from WSDL file and mapping the corresponding relationships between. However, such a corresponding process will be full of repetitive and mechanical property, in order to avoid the artificial error is not necessary and save development time, a gSOAP compiler tools emerge as the times require. GSOAP provides a set of transparent SOAP API using compiler technology, and will be developed with independent SOAP implementation details related to the user to hide. The WSDL file parsing serialized as an C/C++ file, the development process of Web Service to minimize. The concept of ONVIF specification introduces Web Service to video surveillance. The actual function of the equipment are service abstraction to Web Service, the control unit of video monitoring system in the identity of the client, the Web request form to complete the control operation. Web Service can bring what video monitoring system? Device independent, any equipment access system, will not impact on other systems. The independence of the equipment, each device is only responsible for the feedback of the received request, don’t even need to know the existence of the control terminal. Centralized management, all controlled by the client to initiate. The ONVIF specification can bring what video monitoring system? Abstract the function interface. The unification of the equipment configuration and operation mode. The control end is not concerned with the type of equipment, but the equipment provided by the Web Service specification for the Service range of Web video system behavior. ONVIF provides the various modules of the WSDL, has a very high efficiency development. The contents of ONVIF specification Device discovery Equipment management Equipment input and output service Image configuration Media configuration Real time streaming media The receiver configuration Display service Event processing PTZ control Other The application of ONVIF This is a LAN Application of traditional video surveillance system scenarios 1.PU equipment on the line, to the CMU registration, establishing a connection. 2.For the interaction of CMU and PU, request ability set, obtaining configuration 3.CU on the line, to the CMU registration, establishing a connection. 4.For the interaction of CMU and CU, transmission equipment list 5.The CU request to the PU stream The application of ONVIF specification of the corresponding scene: 1.PU equipment on the line, to send the CMU HELLO message. 2.CMU needs to search for the device to send the PROBE message, PU. 3.For the interaction of CMU and PU, request ability set, obtaining configuration 4.CU on the line, to the CMU registration, establishing a connection. 5.For the interaction of CMU and CU, transmission equipment list 6.In coordination with the CMU, CU and PU connection transmission stream In the above scenario, ONVIF bring what changes? Changes in PU and CMU interaction. CMU is no longer with the PU to keep the long connection.

Relation matrix and HD-SDI HD

HD-SDI matrix is a kind of digital video matrix switcher, for the BNC interface, is designed for SDI digital video signal display switching, high performance intelligent matrix switch equipment and produces, mainly used for various image input signal switching to the image output channel in any channel, has been widely used in radio and television engineering, multimedia conference hall, large screen display works, television teaching, command and control center market. This product is generally a power-off protection, and have a RS-232/422 or RS-485 control data interface, can control the main system, convenient to setup the computer, remote control keyboard or with various distance man-machine control equipment used.

The difference with the traditional analog signal matrix
Because the signals from different sources, matrix circuit principle is also different. The traditional matrix is a kind of cross circuit processing structure, and SDI is 1 ∶ 1, 1 ∶ 4 and 1 ∶ SDI image input 8, the distribution amplifier card, plus 4 or 8 SDI sync signal processing, the input and output signal synchronous allocation, the end of the analog / digital converter will convert the signal into NTSC or PAL TV image signal to output to the screen. From the appearance and structure of the equipment point of view, the traditional matrix and SDI matrix almost do not have too big difference, but in the framework of the system, can be found in matrix changes in traditional matrix 6 × 4, 32 × 8, 32 × 16, 64 × 16, 96 × 16, 128 × 32, 256 × 96 and 4096 × 256 etc. more irregular. SDI matrix is currently limited by the signal components and distribution of amplifying rules, its size is about 1 × 4, 4 × 4, 8 × 8, 16 × 16 and 32 × 32, the card in the stack becomes the 64 x 32, 64 x 64, 96 x 32 and 96 x 64, 128 x 32 the rules of structure to. The existing technical conditions with about 128 * 128 as the practical application of the maximum capacity, if want to break through this limit, also required materials equipment and technology to break through.

In general, regardless of the traditional matrix or SDI high resolution matrix, basically is the transmission medium with Belden 1694A coaxial cable as the image signals, and in the transmission and control of PTZ camera and sound, is more than a RS-232/422 or RS-485 duplex or half duplex (Full/HalfDuplex) mode to the control signal to the camera. To type in SDI camera 3G-SDI, manufacturers have sound, power and control signals, leading to the image signal half way, load blank in the image signal, so as to reach a single coaxial transmission matrix requirements, but at present the product technical conditions, the signal transmission distance, still is one of the obstacles of SDI matrix.

SDI matrix system mostly to provide RS-485 protocol, would involve the past in engineering, attention must be paid to the label control protocol (Control Protocol), in the same conditions can be achieved on the SDI high speed ball or machine PTZ control. Keyboard parts on the matrix is controlled by a RS-232/422 or RS-485 network port. SDI matrix products with the same control setting software for this function, in the system setup and operation, can provide users convenient operation management. In the SDI high resolution matrix of long distance and high resolution camera, the system can now through the SDI transmitter composed of loop, construction becomes a real-time digital monitoring system for high resolution, non compression.

Most of the SDI high resolution digital matrix control system, using microprocessor technology, such as the processor of ARM series, and will use the Linux core operating system more stable and reliable, the operation stability of the system. The system can be in SDI routing, support to a maximum of 128 or 256 input, input and output interface SDI 128 output contains the video and audio signals.

As in the image performance, due to the current SDI camera format itself not a, SDI matrix must be considered to be compatible with SDI image signal, receiving 720P or 1080i/1080P@30fps or 60fps at the same time, according to the number of SD or 960H high speed analog analog image signal input to the output, but also to be able to switch, it is SDI imaging performance matrix characteristic, is also the past traditional matrix which can not be achieved.

SDI matrix with different structures, such as modular, plug-in, blade, is the SDI matrix in the development process, source frequently have problems. For example, if the system in a modular card, hot insertion, are related to the stability and reliability of system performance. Of course, the module is one of the best ways, including control, power system, these structures for troubleshooting and system provides the convenience of maintenance. At the same time, because of the modular design, makes the matrix expansion easier stack, both for the convenience of the manufacturers, but also to enhance the production speed, reduce the failure rate of the product, enhance the stability and reliability. In the redundant backup power, control and power system most of the SDI matrix, in addition to the requirements of modular, slot or board structure, at present mostly in the double control, dual power supply, but also has the redundancy backup function, avoid manual backup systems may malfunction worries.

Simulation application of surveillance cameras and the development of new observation

In the field of surveillance cameras, nearly two years although the network camera, HD video camera has become the most popular topic, but in the foreseeable future years, analog camera will still occupies an important share of the market. Especially for the civil demand in general, simulation of infrared camera conventional has its application sites are wide, low price, convenient installation and maintenance, will continue to be ordinary customers preferred. So the conventional infrared camera to have its practical significance to maintain attention, this paper attempts to years development of related technology and application are presented.

1、SONY plan to upgrade
Sony Corp launched Effio-E650 line although there have been three years, but the early because the technology is not mature and the price is too high, BGA processing difficulty, solution and its DSP chip to design the whole circuit requirements higher, so in the two years before the start of the manufacturers are not many. Along with the strengthening of the maturity of the increase, prices continue to fall and the manufacturers of the relevant skills, until the middle of 2011 SONY3172 chip shortage, most of the CCD board or camera manufacturers began to vigorously promote the Effio-E scheme. Because of its higher image resolution, color reduction degree and higher signal-to-noise ratio, application of Effio-E scheme quickly recognized by the market; SONY and at the end of 2011 the introduction of enhanced Effio-E scheme version. The single material from the cost of speaking, its price has no difference scheme and SONY3172 scheme, Effio-E scheme of CCD plate sales but often causes a slightly higher price is the BGA process leads to the high cost of repair repair.
In addition to the Effio-E program, digital wide dynamic Effio-S scheme, Sony Corp also has really wide dynamic function of Effio-P double scanning scheme, also obtained the different degree of promotion. And in CCD, Sony has released the recent replacement of 673 811CCD, continues in the package to improve.
Note: BGA is the abbreviation of “BallGridArrayPackage”, namely the spherical pin grid array package technology. Is the original chip traditional from around the elicitation of the J shaped or wing condition changed from spherical pin chip bottom plane extraction, the chip body abdomen beneath become grille type pin array the whole plane. Its main advantage is to increase the distance between the pin when the pin number, improve the rate of finished products of the chip; in addition to reduce the signal delay, greatly increased the frequency.

2、The application of CMOS to further expand
This year, the biggest change should promote CMOS chip is in the industry status. Previously in the concept of people CMOS sensitive chip and the effect is poor, cheap is linked together, but with the application of high definition camera to be popularized energetically, CMOS sensitive chip is superior to the CCD photosensitive chip with the “HD” also be market awareness.
First we need to know about CMOS and CCD working mechanism of different. When the CCD works millions of pixels photo generated millions of charge, all by an amplifier voltage transformation, the formation of electronic signal by a channel output, when a large amount of data is prone to signal congestion. The CMOS sensor each pixel consists of a single amplifier output, capable of handling large amounts of data in a short time. So in the face of high-definition video data transmission performance requirements, CCD cannot meet the demand of HD camera because of its own transmission bottleneck.
In 2012, in the field of analog camera, the promotion industry leading manufacturers of 600TVL CMOS1089 scheme, in the well-known brand reputation and support, project developers and user level began to view the CMOS1089 high price. And user acceptance in turn promoted CMOS600TVL camera demand and production, so that to the chip supply situation.

3、The NextChip scheme matures
NextChip is a South Korean chip research and development company, launched in the surveillance camera of DSP can match the Sony CCD. But due to the poor overall effect in the early years of the scheme, although initially some manufacturers in the promotion, but has not been recognized by the market. But after the NextChip version 10 consecutive times continuously upgrade, its performance has been greatly improved, the color, clarity has very close to or even more than at the SONYDSP effect, very suitable for the simulation control system. At the beginning of 2012, NextChip further released a new scheme of NVP2030E, NVP2040E, new solutions to the NextChip relative to the SONYDSP’s biggest: when the chase light lens Daytime Outdoor Exposure problem. Plus NextChip has a menu function, such as lens types optional, optional exposure, white balance, processing, switching, and backlight spot repair, and reversing auxiliary line to compare the special function, provides the possibility for the special application environment in some of the requirements is not very high. In addition the NextChip chip sales prices compared to the Sony Corp is also much lower, for scheme selection of camera manufacturers showed a good cost-effective competitive advantage.

4、The new scheme has the special function of AVS
Different from the traditional program focuses on the definition, upgrade continuously upgrade, AVS in Taiwan, the new DSP has a new face recognition function, very attract sb.’s attention. The scheme to image feature built-in face images, and then search the image with facial feature regions, find the location and its electronic amplification, the center of the screen shown in. In the AVS scheme, a face is electronic amplification often resolution is not high enough; in the upgrade program in new because the overall picture clarity has been significantly improved, the face of the enlarged image can still maintain a relatively high definition. In the new scheme of AVS, also can face continuous storage to grab the “face book” function, and can set the virtual partition line “electronic fence” function. Wide dynamic AVS solutions also can provide 120 frames / second shooting speed, also showing a very ideal effect.
Although the new scheme and there are many areas in need of improvement in the technical details, but through the DSP chip to realize the face recognition and amplification of this new ideas, evolution of the DSP scheme for the long-term lack of innovative process adds a bright spot. Believe that with the technology to mature, this kind of function applications add new products, the scheme will be a large number of users use.

5、IR-CUT performance improvement
In order to improve the image color, especially in the CMOS scheme, IR-CUT device (i.e. double filter) is widely used in. IR-CUT is composed of a infrared shielding filter and a full transparent spectral filter and switching power part. The key factor to determine the quality of IR-CUT is switching power part, there are mainly two: electromagnetic type and motor type. In general the electromagnetic low cost, but its stability is poor; stability of motor, mechanical part of higher cost will be higher. Many IR-CUT manufacturers say their products can be normal switching more than one hundred thousand times, but for the camera, even by 5 years of working life longer, only need to switch 4000 times is enough. So for the IR-CUT device, important is not the switch in the best working condition number, but squeezing, high temperature environment work in the life of the possible installation. But the market response using the actual look, IR-CUT stability now camera has been increased for.

6、The conventional fixed lens clarity to further enhance
For the infrared camera lens in the MTV routine, some manufacturers have introduced megapixel lens and normal lens price difference between the smaller, creates convenient conditions for the ordinary camera performance of conventional promotion. In addition there are 2000000 new pixel lens shape, the upper part of the lens, such as CS interface to MTV interface. At present, this kind of lens is only 4mm, 6mm, 8mm three specifications. The HD lens transparent glass multi-layer plating technology uses six storeys high, higher, than megapixel lens imaging resolution before night vision effect real soft, color reduction degree is better.

7、Enhance the overall quality of high power IR-III lamp
Although IR-III high-power lamp (there are a lot of people known as the “third generation matrix infrared”, actually this is not the same as the two) there have been more than two years, but many manufacturers until nearly a year to really put the new infrared light board do mature. The main parts of IR-III infrared light board cost is relatively high, last year, many manufacturers in order to improve the product price advantage, have adopted various methods of cost saving. Product design is not a strict often buried many hidden dangers, in use after a period of time, many problems are exposed. Finally be able to remain invincible in the product is to follow the law, the principles of scientific design, quality priority of careful material selection based on, from the wick, aluminum plate, lens, control panels, each technical points of each component of the effort, really solve the wick high standard selection, control board, lens two times with stable power supply light, and good heat dissipation and other key issues, to the brightness of IR-III high power infrared technology is high, long life advantage. On the basis of constantly sum up experience, now the overall IR-III technology to master degree has been greatly enhance the stability of the manufacturers, IR-III light plate generally improved.
Note 2: infrared array technology is using a plurality of high efficiency and high power chip is packaged in a plane, consisting of a plurality of chips. As a result of a lens only a center of a circle, many light source can not be all light gathering to a focus lens is sent, so the light is scattered, which caused a lot of infrared light is wasted, resulting in infrared effective utilization rate is not high. IR-III is a single chip light source, out through the lens to send, concentrated light, uniform, reach 100% utilization, the luminance of IR-III technology to high brightness than the array type.

8、The emergence of a large number of new housing
In the intense competition of market, the camera manufacturers in addition to the camera movement on the efforts, efforts to seek changes in the appearance of the. With respect to break through the camera kernel performance, although the mold development costs are high, but from a technical perspective, the appearance of a breakthrough more often than scheme, infrared light, break more easily. With dot matrix LED have higher requirements in the heat, many new housing design not only because of the beautiful, special purpose, heat treatment led to better has become an important driving force. The number of new housing this year, far more than can be said before the year. The new shell appears in three forms, the simplest is the color changes in the original mold, such as oxidation except color original processing, fuel injection, powder injection technology are widely used, even a “injection treatment camouflage outfit”; second is a small change in the outer shell structure the tail from the flat, such as changing as convex, convex to flat, or the rain hood make some changes; the third is the new mold design, in this kind of new design in a lot of imaginative products. But not all the changes, innovation can be recognized by the market, some change or innovation is not moved by the user, finally can’t really use up. Because of the emergence of new appearance, allowing the camera to the industrial products are becoming more and more full of modern fashion.

Basic knowledge of surveillance cameras

1、Surveillance cameras are generally divided into several parts: shell, bracket, lamp, lens, circuit board.
The circuit board is the most important part in the surveillance camera, a monitoring camera appearance to be the same, but the price and the effect has a world of difference, this is the reason why different circuit boards, surveillance camera circuit board is corresponding camera monitoring scheme, it is the different schemes have different circuit boards.
At present domestic surveillance camera scheme has 2 kinds, one kind is CMOS; a CCD scheme.
The COMS scheme in the specific circuit board production, and is divided into many, such as the PC1030 scheme.
Surveillance camera imaging effect of CMOS regimen in general, color is white, color reduction degree and the detail of the picture processing capabilities are not very strong, a lot of methods to identify CMOS scheme, CMOS scheme for general circuit board because the circuit is simple, are double-sided board, board size, board a small chip.
The CCD scheme is a scheme on the market at present is relatively mature, CCD is the optical silicon semiconductor imaging, the above scheme the market to see the most is the SONY scheme and SHARP scheme, namely everybody says is the SONY chip and the SSHARP chip.
SHARP generally refers to the SHARP chip 1/4 sensor, there are 1/3 sensors, but the market is rare, the chip is SHARP38603 main chip SHARP2421 sensor, SHARP imaging effect is ideal, the color reduction degree is also very realistic, compared with the SONY scheme, is the image color is brilliant, with the higher price surveillance camera this scheme, difference method is directly disassemble look big chip on the circuit board is it right? SHARP38603 (sensor model is in the sensor bottom, disassembly is not to see).
The SONY scheme is relatively complex, SONY420 line, SONY480 line, SONY540 line, SONY420 line was divided into 1/3 and 1/4, the 1/3 and 1/4 refers to the size of the sensor, the sensor is the diagonal length is 1/3 or 1/4 inches. SONY420 line 1/4 specific chip SONY3142 main chip CXA2096SONY227 sensor, SONY420 line 1/3 specific chip SONY3142 main chip CXA2096SONY405 sensor, the distinction between the 2 is a sensor size, 1/3 imaging effect is better than 1/4.
The SONY480 line is available on the sellers emphasize HD camera, the specific chip SONY4103 main chip CXA2096SONY409 sensor, imaging imaging effect of SONY480 line than the SONY420 line on a grade, SONY480 line imaging than 420 line should be soft, color is more realistic, so the price is also expensive many, must be clear, is the SONY420 line or SONY480 line, 480 line, what is the chip, this is very important. The difference between SONY540 and SONY480 line is not great.
The specific chip SONY520 line of SONY3172 main chip CXA2096SONY409 sensor. IR plays a decisive role in surveillance cameras night vision.
Infrared light from the appearance of the above points, &3, &5, &8, &30, this number refers to the diameter of the body of the lamp, the unit is mm.
The commonly used &5 and degree of distinction degree 30 degrees, 45 degrees, 60 degrees, 75 degrees, 90 degrees. The higher the degree, strength is far infrared ray emission corresponding is weak, for 15 meters, is generally 45 degrees, in the distance (15 to 30 meters) is generally 60 degrees infrared lamp.
Long distance word is more than 60 degrees, but in the middle and long distance, in order to let into the distance with infrared good effect, can be used to mix light, is light board has more than 2 kinds of infrared lamp. At present a lot of infrared lamp brand, is Taiwan Ding round wick better quality, we should note here is the wick brand is Ding round, rather than being brand is Ding circle. The number of surveillance cameras, infrared light is generally 12, 24, 36, 48, &5 type infrared lamp, night vision distance of 12 infrared light is 10 to 15 meters, the effective distance of 24 infrared night vision is 20 to 25 meters, the effective distance of 36 infrared night vision is 30 to 35 meters, 48 infrared light is 40 to 50 meters, to night vision to see far, in addition to the selection of a high-resolution camera, can also choose the infrared light, such as 6 &8 infrared lamp plus SONY480 line 6 &30 lamp with the scheme with 25mm above the lens, night vision distance can reach 80 to 100mm.
Lens relative circuit board is easier, the lens can be divided into focus and non focus, for most buyers, not focusing can meet the requirements, not focusing lens and 3.6mm, 6mm, 8mm, 12mm, 16mm, 25mm, 32mm, 50mm.
Focal length is small, see the bigger, but imaging observation of objects smaller, observation distance is closer, generally on the indoor shops, choose 3.6mm or 6mm, the corridor or distant observation points to more than 6mm lens, 25mm lens with a SONY480 wire or 520 wire scheme, can see about 60M a day face. In the choice of lens to choose according to the actual situation of their own.
(1)The resolution is an important parameter to evaluate the quality of the camera, which is when camera arrangement interval of black and white stripes, on the monitor can see human maximum line number, if more than this line number, the screen can only see and can’t distinguish between black and white lines on a gray. Clarity is divided into horizontal resolution and vertical resolution.
(2)Test method, camera test chart, using the visual method was used to observe the maximum line biggest line monitor image center wedge can be distinguished as number or ten groups of central definition segment can distinguish the number.
(3)Attention should be paid to the test
A、 to use the good imaging quality lenses, because the lens can affect the final test results.
B、the use of black-and-white monitor display, line number should be in 600 above, if the use of color monitor, the color saturation knob to the lowest, avoid interference color signal for a luminance signal.
(4)Should pay attention to when purchasing
A、 the use of Sony, Panasonic original camera to do lateral comparison, observation of two camera gap in resolution black and white lines group; performance index of the original machine is reliable, by contrast, can the definition index to buy the camera to get the correct conclusion.
B、the purchase of single board computer, sometimes lens imaging quality is poor matching, in addition to the test center resolution, or test four angular resolution, cannot appear fuzzy and deformation, otherwise, will replace the good lens.

2、Minimum illumination index have the related conditions
(1)The concept of minimum illuminance, luminance output level generated by a video camera, was rated level (700mV) of the half, minimum illumination object.
(2)Test method
Ten gray level test card
A、Method: the camera. In the darkroom, choose the original camera a factory to compare, use two of the same model manual iris lens, 220V incandescent lamp anechoic chamber with pressure regulator control, to regulate the voltage regulator to adjust the height of the darkroom lamp shade, voltage can be 220V from 0V to, the indoor light is also available from the dark to the light, the two cameras are respectively aligned to the object level of rich, brightness to reduce indoor, until can’t see objects in the black level, or the lens aperture smaller level for comparison, according to the minimum illumination original camera factory of the nominal value that the lowest the measured values of the illumination camera.
B、Method: the same test instrument in the dark, the camera at the ten level grayscale test card, optical brightness down the room, until the camera output video signal on the oscilloscope amplitude to 350mV, then the meter measuring test card surface illuminance values, calculated the minimum illumination.
(3)Should pay attention to during the test was numerically lowest illuminance is related with the following four factors.
A、The aperture of the lens
B、The color temperature of light source
C、Video signal amplitude
D、Albedo (reflectivity of target and background)
The only marked the above four conditions, the lowest illuminance testing that is meaningful, not set aside the four test conditions and a simple comparison of a certain brand of camera illumination nominal value and another brand of camera illumination nominal value to compare, better low light performance otherwise cannot draw conclusions which camera.
(4)Should pay attention to when purchasing
Select the illumination camera: nominal minimum illumination only for reference, the key is to choose the appropriate camera according to the need to use the occasion. Use the lowest illuminance meter measuring site. Simulation of light field in the darkroom, choose a different camera test or the use of large aperture lenses, to distinguish gray test card of ten level contour.

3、Relationship between height and illuminance of SNR
(1)The so-called “signal to noise ratio” refers to the ratio of signal to noise voltage voltage, usually represented by the symbol S/N. Signal to noise ratio is divided into ratio and signal-to-noise ratio of signal to noise of color brightness. One of the main parameters of the signal-to-noise ratio is also a camera.
When the camera is bright scene, monitor display picture usually is more lively, the observer is not easy to find out the interference noise in the picture; and when the camera is dark scene, monitor display screen is dark, the observer and it is easy to see the interference noise snowflake in the picture. Camera with higher SNR, influence of interference noise on the image of the smaller.
(2)Detection method for luminance signal to noise ratio
A、Simple discriminant method
Luminance: the signal-to-noise ratio of the aperture of the lens is closed, or cover the lens cover, the number of observation of interference noise snowflake on the monitor.
Chroma signal to noise ratio: the cameras at the white balance test card, much noise observation with color.
B、Comparative method
The camera. In the darkroom, choose the original camera a factory of the comparison, the use of two same types of manual iris lens, put the camera and the original camera at the black balance test card, adjust the light intensity with the size of the dimmer, the interference noise snow flower and visible until the picture, comparison of noise the point density and size, numerical estimation of signal-to-noise ratio.
C、Instrument method
Brightness signal to noise ratio: the camera at the ten level grayscale test card, adjust the aperture size, the video level camera output reached 350mV, the signal access video noise measuring instrument, reading SNR read directly on the dashboard
(3)Attention should be paid to the test
A、The choice of filter, using 100KHZ low pass and FG high pass, do not use video weighting curve.
B、To consider the effect of AGC and R camera calibration.
(4)Should pay attention to when purchasing
Since the video noise measuring instrument is expensive, domestic manufacturers generally do not have such equipment, large manufacturers using the oscilloscope to estimate the size of the signal to noise ratio, many manufacturers visual camera small snowflakes point, just fill out a digital, chroma noise measurement is impossible.
Therefore, in the purchase of the camera, the camera should be chosen according to the illumination conditions using the site, use a light meter to measure and record, different illumination using site in the monitoring period value. To simulate different illuminance values using site office darkroom, observation noise points which a camera, increasing the aperture of the lens or the use of a large-diameter light lens, or is the increased use of location of the brightness of the light, the display until the monitor image quality to an acceptable level, which is fit for you to use the camera.

4、Automatic white balance and color adjustment
Color bar test card
(1)Color camera color reduction is the most important factor determining the picture quality. The shooting object red, green, white, blue three primary color signal voltage output by the camera: VR= VG=VB of the phenomenon known as the white balance.
Automatic white balance, color temperature of light as the sun in the morning, noon, afternoon, the different period is different, all kinds of artificial light source color temperature high and low temperature, color cameras in different circumstances, should correctly reproduce white, this needs correction of white balance at any time in continuous work.
White balance is an important parameter of color camera, good CCD can restore the scenery very good color, make the object look clear; when the camera white balance is poor, to reproduce the image will have partial color phenomena, especially can make originally not coloured objects (such as white walls) is a color.
(2)Detection method of white balance
A、Visual method
Manual white balance: panel switch superscript camera 3200K, 5600K words, show white balance adjustment of the camera is according to 3200K color temperature and color temperature of 5600K were layout.
Use the same color of the artificial light source (such as tungsten halogen lamp or fluorescent lamp), cameras at the white balance test card, observe whether partial color on a monitor screen.
Automatic white balance: cameras are aligned in two different color temperature light white balance test card, or the installation of 3200K and 5600K color temperature conversion filter in front of the camera. Whether the white balance of color on a monitor can be restored to the original white, observation camera automatic white balance conversion speed.
B、Instrument method
The camera at the standard color temperature light box color test card, the signal access to vector oscillograph, whether the six spot observation shows that falls under the provisions of the vector point, through the spot position. And the amplitude of the camera red, green, blue, yellow, green, six colors whether partial color and color saturation.
(3)Attention should be paid to the problem of testing
Camera white balance performance, performance for the scenery being shot on the monitor color reduction, which requires a premise that monitor, not partial color, otherwise it cannot determine the camera color; use video signal test disc, the output of a white field signal to the monitor, observe the screen white whether partial color.
(4)Attention should be paid to the problem of procurement
The camera should pay attention to the light source color temperature changes and monitor color to display image size, does affect the monitoring effect, can adjust the white balance adjustment circuit monitor or adding color before the cameras adjust filter.
Minimum illumination, resolution, signal-to-noise ratio and white balance is the most important technical indexes of camera, buy according to four indicators, combined with price considering.
Cameras in this circle, technical indexes of color pages, it has covered most of the technology, not the letter, there are few people dare to say that he knew, regardless of sales or engineering business, first to get is a color, but the color pages, most just bragging, only in the technical indexes the last is “slightly” some knowledge, today will take everyone to do:
Is expected to “knowledge” and “actual combat”, knowledge me, actual papers by you to provide information, everyone together to practice, most manufacturers may also participate in together, add some interesting…

Monitor camera principle

Chapter 1   The security monitoring equipment
Part 1    Video camera
1、Working principle
In closed-circuit monitoring system, video camera and camera or CCD (Charge Coupled Device) or charge coupled devices. Strictly speaking, the camera is a camera and lens, but in fact, the camera and lens is mostly purchased separately, the user according to the size of the object and the camera and the object distance obtained by calculation, the focal length of the lens, so each user needs lens are determined according to the actual situation, do not think that the camera (head) has a lens.
The main sensor camera is CCD, it has high sensitivity, small distortion, long life, anti vibration, anti magnetic field, small volume, no ghost features, CCD is a charge coupled device (Charge Couple Device) for short, it can be light to charge and the charge storage and transfer, can also be storage charge taken to voltage changes, so it is the ideal imaging element. Is a new type of device for camera tube sensor.
The work principle of CCD is: object reflects light, spread to the lens, the lens focusing on the CCD chip, CCD according to the light intensity of the corresponding charge accumulation, the periodic discharge, produce electrical signals indicative of a picture, after filtering, amplification, composite video signal output by a standard output terminal camera. The video signal of the standard with the home VCR, VCD machine, home video camera video output is the same, so we can watch the video or from tv.

2、CCD classification
Selection and classification of CCD camera
The CCD chip as the human retina camera, is the core of. At present our country has no ability to manufacture, market, most of the cameras are used in Japan SONY, SHARP, Panasonic, LG, chips, now South Korea also has the ability to produce, but the quality will be just a little bit worse.
Because the chip production by different levels, the manufacturers access to different reasons, the effect of CCD acquisition is not the same. At the time of purchase, we can adopt the following methods:
Switch on the power, connect the video cable to the monitor, to close the lens aperture, see the image black is bright, snow big screen, the detection of CCD chip is the most simple and direct method, but no other special instruments. And then you can open the aperture, a still life, if it is the best color camera, take a brightly colored objects, image viewing on the monitor whether partial color, distorted, or whether the smooth gray color. Good CCD can restore the scenery very good color, make the object looks clear and natural; and the image of defective products will have partial color phenomena, even in the face of a piece of white paper, the image will appear blue or red. Individual CCD due to dust production workshop, there will be CCD impurity on the target surface, in general, the impurity does not affect the image, but in the weak light or micro camera, fine dust can also cause adverse consequences, if used for such work, must be carefully chosen.
(1)According to the imaging color partition color camera: is suitable in the scene detail discrimination, such as discrimination in dress or color features.
(2)In accordance with resolution sensitivity into image pixels below 380000 for the general type, among which 250000 pixels (512*492), a resolution of 400 lines are the most common. Image pixel in more than 380000 high resolution type.
(3)According to the size of the CCD target surface partition of CCD chip has developed a variety of size:
At present the majority of 1/3 “and 1/4 chip”. In the purchase of camera, especially when there are strict requirements on camera angle, the size of the target surface with CCD, CCD and the lens will directly affect the view angle and the size of the image definition. 1 – inch – target size width 12.7mm* high 9.6mm, diagonal 16mm.
2/3 inch – target size width 8.8mm* high 6.6mm, diagonal 11mm.
1/2 inch – target size width 6.4mm* high 4.8mm, diagonal 8mm.
1/3 inch – target size width 4.8mm* high 3.6mm, diagonal 6mm.
1/4 inch – target size width 3.2mm* high 2.4mm, diagonal 4mm.
(4)According to the scanning system partition of PAL system, NTSC system.
China adopts the interlaced scanning (PAL) system (black CCIR), standard for 625 line, 50 games, only the medical or other professional field will use some non-standard mode. In addition, the Japanese NTSC standard, 525, 60 (black EIA).
(5)In accordance with the power supply division of 110V (NTSC system many of the), 220VAC, 24VAC. 12VDC or 9VDC (micro camera multi category).
(6)Divided by the synchronous mode
Internal synchronization: to complete the operation with synchronous signal camera occurs within the synchronization signal generated by the circuit.
External synchronization: the use of a synchronization signal generator, synchronous signal into the camera out of sync input. Power synchronous (linear lock, line lock): vertical driven synchronous with the completion of the camera AC power. VD synchronization: the camera signal cable VD synchronous pulse input complete VD synchronization.
The multi camera synchronization: synchronization of multiple cameras fixed, so that each camera can work under the same conditions, synchronization due to the camera, so that even if one camera conversion to other scenery, synchronous camera footage nor distortion.
(7)According to the degree of division, CCD is divided into: the intensity of 1~3LUX to ordinary work
The moonlight type:Required for normal illumination about 0.1LUX
The star type:The intensity of 0.01LUX to work the following
Infrared type:Using the infrared lamp lighting, in the absence of light conditions can also be imaging
(8)According to the appearance: organic plate, needle pass, hemispherical.

3、Technical indicators
The main technical indexes of CCD color camera
(1)CCD size, i.e., the camera target plane. The 1/2 inch, 1/3 inch now has popularization, 1/4 inch and 1/5 inches has also been commercialized.
(2) the CCD pixel, is the main performance index of CCD, it determines that the clarity of the image, the higher the resolution, the better the image details. CCD is composed of a planar array photosensitive elements, each element called pixels, the more pixels, image more clear. Now on the market mostly in 250000 and 380000 pixels for the delimitation, more than 380000 pixels for high definition camera.
(3) the horizontal resolution. The typical resolution color camera is between 320 to 500 TV lines, mainly there are different grades of 330 lines, 380 lines, 420 lines, 460 lines, 500 lines.
Resolution is the television line (referred to as TV LINES) to represent, color camera resolution between 330~500 line. Resolution associated with CCD and the lens, and camera circuit channel band width is directly related to the usual rules, 1MHz band width is equivalent to the definition of 80 lines. The frequency band is wide, image more clear, relatively larger numerical.
(4) minimum illumination, also known as sensitivity. Is the sensitivity of the CCD to the ambient light, or that is needed for CCD imaging of the dark. The unit of illumination is lux (LUX), with smaller values, expressed the need for less light, the camera is also more sensitive. The moon and star level high sensitivity camera can work in very dark conditions, 2~3lux general illumination, also now have ordinary camera than the appearance of 1lux.
(5) the scanning system. PAL system and NTSC system division.
(6) the camera power supply. AC 220V, 110V, 24V, 12V or 9V dc.
(7) signal to noise ratio. The typical value is 46db, if 50dB, then the image with a small amount of noise, but the image quality is good; if 60dB, then excellent image quality, no noise.
(8) the video output. For 1Vp-p, 75 Ω, adopt BNC joint.
(9) lens mount. There are C and CS, among the two difference is that different photographic distance.

4、Adjustable function
1.Can adjust the function of CCD color camera
(1) synchronization options
A、the single camera, there are the following three kinds of main synchronization:
Internal synchronous — generates the synchronization signal to complete the operation by crystal oscillation circuit inside the camera.
External synchronization–To the camera using a synchronization signal generates a synchronization signal generator and synchronous input to realize synchronous.
Power synchronization — also known as linear locking or row locking, is the use of AC power to complete the vertical driven synchronous camera, the camera and the power zero line synchronization.
B、For multi camera systems, like video input signal is all vertical sync, so in the converter camera output, will not cause image distortion, but due to the various camera power supply multi camera systems may be different from the phase of three-phase power, and even the whole system with the AC power is not synchronized, then we can take some measures:
Using a synchronization signal generation with a synchronization signal generator into the camera external synchronization input to adjust the synchronization.
Adjust the camera “phase adjustment potentiometer,” due to camera in the factory, the vertical sync with rising edge is zero phase current, the phase delay circuit can make each camera have different phase shifts, so as to obtain the vertical synchronization suitable, phase adjustment range 0~360 degrees.
(2) automatic gain control
All the cameras have a signal from the CCD amplifier to use video amplifier level, which is equivalent to the amount of gain, sensitivity is high, can make the light sensitive, but the amplifier in the light environment will overload, the video signal distortion. Therefore, to control the automatic gain camera (AGC) level circuit to detect the video signal, timely switch AGC, so that the camera can be in the larger illumination range, the dynamic range, which increases the sensitivity of the camera automatically in low light, to obtain the clear image and improve the image signal from the strength.
(3) the background light compensation
Usually, the camera’s AGC operating point is based on the entire field of content to determine if the average, but contains a very bright background region and a very dark foreground in the field of view, is at this time to determine the AGC working point may be not suitable for foreground, background light compensation may improve the foreground display status.
When the background light compensation is turned on, the camera only on the whole field of a sub regional average to determine its AGC operating point, if the foreground object is located in the sub region, visibility of the foreground object is expected to improve.
(4) electronic shutter
In the CCD camera, with optical electronic imaging surface charge accumulation time to control the shutter. Cumulative time electronic shutter control camera CCD, when the electronic shutter is closed, the NTSC camera, the CCD cumulative time is 1/60 seconds; for PAL camera, for 1/50 seconds. When the electronic shutter camera is open, for the NTSC camera, the electronic shutter to 261 step coverage from 1/60 seconds to 1/10000 seconds; for the PAL camera, the shutter with 311 step coverage from 1/50 seconds to 1/10000 seconds. When the electronic shutter speed increases, the time for each video field within the allowed, focusing on CCD light is reduced, it will reduce the camera sensitivity, however, higher shutter speed for the observation of motion image will produce a “stop action” effect, which will greatly increase the dynamic resolution and camera.
(5) the white balance
White balance is only used for color camera, its purpose is to realize the camera images can accurately reflect the scene situation, manual white balance and automatic white balance in two ways.
A、automatic white balance
Continuous mode — the white balance setting with the features of color changes in temperature and continuously adjusted, the range of 2800~6000K. Is the most suitable way for scenery color temperature during filming changing situations, color is natural, but with little or no white scenery, white balance can not continuously produce the best effect of color.
Button: first the cameras such as white wall, white white target, and will automatically switch from manual dial to the setting position, is retained in that position for a few seconds or until the image appears white, to be performed in the white balance, will automatically switch to manual position to lock the white balance settings, the white balance setting will remain in the camera memory, until re execution is changing so far, its range is 2300~10000K, in the meantime, even when the camera power does not lose the set. The button to set the white balance is the most accurate and reliable, and is suitable for most applications.
B、Manual white balance
Open the manual white balance will turn off the automatic white balance, then change the red or blue state image as many as 107 grades for adjustment, such as increase or decrease the red one each level, increase or decrease the blue one for each grade. In addition, there will be some camera white balance is fixed on the 3200K (incandescent lamp level) and 5500K (daylight levels like command).
(6) the color adjustment
For most applications, is not the need for camera color adjustment, such as the need to adjust to carefully adjust so as not to affect the other color, adjustable color mode:
The red – yellow color, the red to pink move a step.
The red – yellow color reduction, the red to yellow to move a step.
Blue – yellow color added, the blue to green blue step.
Blue – yellow color reduction, the blue ocean of red to move a step.
2.Adjust the control method of digital type
Digital control by adjusting the new camera on the optional parameters, then do not have to manually adjust the potentiometer instead of using auxiliary control code, and these parameters are stored in digital memory unit, to increase the stability and the reliability of the.
The DSP camera into the part of digital processing technology in the simulation system of the foundation, known as digital signal processing (DSP, DIGITAL SIGNAL PROCESSOR) camera. The camera has the following advantages:
(1) and intelligent background light compensation function due to the adoption of digital detection and digital computing technology. Conventional camera shot a scene at the center of the screen to requirements and to occupy larger area party can have the background light compensation better, otherwise the bright background light may reduce the transparency of the image center. The DSP camera is a picture is divided into 48 small processing area to detect the targets effectively, so even if is very small, very thin or not in the center area of the scene can be clearly shown.
(2) because of DSP technology and automatic tracking white balance, which can be in any condition detection and tracking “white”, and a digital processing function to reproduce the original color. Traditional camera because of the average treatment on all color screen, so if the color object occupies a large area in the picture, so color reproduction will not balance, also is not able to reproduce the original color. The DSP camera is a screen is divided into 48 small processing area, so it can effectively detect the white screen, even if only a small piece of white, the camera can track it to reproduce the original color. During the filming of grid shaped objects, image can be caused by camera noise aliasing is reduced to the minimum.

5、The selection of cameras and main parameters
The camera lens is the key equipment of video surveillance system, its quality directly influences the whole (index) index, camera camera lens therefore, appropriate selection of which is related to the quality system, and related to the project cost. The lens is equivalent to the human eye lens, if there is no lens, eye cannot see any object; if no lens, then the camera image output is a vast expanse of whiteness, no image output clearly, this principle and we home video camera and camera is consistent.
When the eye muscles can not be lens stretch to the normal position, it is often said that the myopia, the scenery is blurred; with the camera and lens has a similar phenomenon, when the image is not clear, the focus can be adjusted after the camera, changing the distance of CCD chip and the lens (a reference surface to adjust the position of the eye lens), the fuzzy image becomes clear. Thus, lenses in closed-circuit monitoring system is very important. Engineering design and construction personnel must often deal with lens: designers to calculate the focal length of the lens according to the object distance, image size, construction personnel often carries on the scene debugging, which is part of the lens is adjusted to the best state.
(1)Shot classification
According to the shape function is divided according to the size of the aperture is divided according to the type of the zoom focal length divided by the moment
Spherical lens 1 “25mm automatic aperture zoom lens
Aspheric lens 1/2 “3mm manual aperture manual zoom lens
Pinhole lens 1/3 “8.5mm fixed aperture fixed focal length the wide-angle lens
2/3 “17mm fisheye lens
A、Mounting classification to lens
Camera lens all are threaded, CCD camera lens is provided with two kinds of industry standard, namely C and CS mounting seat mounting seat. The threaded part of the same, but both to the photosensitive surface distance from the lens of different.
C installation: installation datum from the lens to the focal distance is 17.526mm.
CS installation: installed special C, this should be the camera in front of the washer and then removed the lens mounted. The lens mount reference surface to the focus distance is 12.5mm. If you want to put a C mount lenses mounted to a CS installation seat camera, you need to use a lens converter.
B、The camera lens specifications
Camera lens specifications should be regarded as the camera CCD size and decide, the two should be corresponding. The CCD target surface size camera is 1 / 2 inches, the lens should be 1 / 2 inch. The CCD target surface size camera is 1 / 3 inches, the lens should be 1 / 3 inch. The CCD target surface size camera is 1 / 4 inches, the lens should be 1 / 4 inch.
If the camera lens size and CCD target size is inconsistent, point of view will not comply with the design requirements, or focus on problems such as the picture outside.
C、Classification to the lens aperture
Lens with manual aperture (Manual Iris) and automatic aperture (auto iris) points, with the camera, manual iris lens suitable for applications in the same brightness, auto iris lens for brightness changes the aperture will be automatically adjusted, so suitable brightness occasions. Auto iris lens has two kinds: one kind is a video signal and power from the camera is transported to the lens to control the lens aperture, known as the input for the video, the other is the utilization of the DC voltage to directly control the camera aperture, called input type DC.
Auto iris lens on the ALC (automatic camera control) to adjust for setting the metering system, can the average brightness of the picture, can screen the brightest part (Feng Zhi) to set the reference signal strength, supply automatic aperture adjustment. Generally speaking, ALC has been in the factory set, can not be adjusted, but for the shooting scene contains a target image with high brightness, bright objects may cause “white clip” phenomenon, and that all the screen turns white, at this time can be adjusted to change the picture ALC.
In addition, auto iris lens with the aperture ring, rotating aperture ring, the lens will change the luminous flux, luminous flux namely aperture, general F, the value for the lens
Jiao Ju and the lens aperture ratio, namely: F = f (Jiao Ju) / D (real effective aperture lens), the F value is smaller, the larger the aperture.
Using auto iris lens, is the ideal choice for the following applications, they are: in such as the sun is very bright, with auto iris lens can have a wide dynamic range.
Requires a good focus on the horizon, with auto iris lens have greater than fixed iris lens depth of field. In light of fuzzy because of the light signal causes the most hours, should use the auto iris lens.
D、The field size classification of lens
Standard lens: from the angle of 30 degrees, in the 1 / 2 inch CCD camera, standard lens is set to 12mm, in the 1 / 3 inch CCD camera, standard lens set to 8mm.
Wide angle lens: the above 90 degree field of view, the focal length can be less than a few mm, can provide visual broad.
Telephoto lens: from the angle of 20 degrees, the focal length of up to a few meters or even tens of meters, this lens objects can be photographed in the distance amplification effect, but the smaller range of observation.
Zoom lens (zoom lens): also known as the telescopic lens, a manual zoom lens and electric zoom two. Variable focus lens (vari-focus lens): it is between the standard camera with wide-angle lens, focal length continuously variable, distant objects can be amplified, but also can provide a broad view, the monitoring range increased. Zoom lens can be set through the automatic focusing on minimum focal length and the maximum length of two position, but from the smallest to largest focal length focusing between focal length, will be achieved by manual focus.
Pinhole lens: lens of a few millimeters in diameter, can be concealed installation.
E、From the lens focal length divided
Short focal length lenses: due to the incident angle is wide, can provide a more broad perspective. In focal length lens: standard lens, focal length as the size of the CCD set.
Telephoto lens: due to the incident angle is narrow, it can only provide a narrow view, suitable for long distance monitoring. Zoom lens: usually electric type, can be used for wide-angle, standard or Yuanwang, lens.
(2)Select the technical basis of lens
A、The size of the imaging lens
Should be consistent with the camera CCD target size, as mentioned before, there are 1 inch, 3 inch, 2 / 1 / 2 inch, 3 inch, 1 / 1 / 4 inch, 1 / 5 inch size.
B、Lens resolution
The inner index describes the lens image quality is the lens optical transfer function and distortion, but the support, needs to understand only the spatial resolution of the lens, to the number of black and white striped per mm can resolved as the units of measurement, calculation formula is: the lens resolution N = 180 / format height. Due to the size of the camera CCD target surface have been standardized, such as 1 / 2 inch camera, the target face is 6.4mm wide * high 4.8mm, 1 / 3 inch camera width 4.8mm * 3.6mm. So the CCD target to 1 / 2 inch format, the minimum resolution of the lens should be 38 on line / mm, 1 / 3 inch format camera, camera resolution should be greater than 50 on the line, the target face camera lens on the smaller, the higher the resolution of.
C、The focal length of the lens and the camera angle according to the monitored distance to the target, choose the focal length of the lens, the focal length of the lens f is determined, the camera target plane determines the view.
D、The aperture or flux
Light transmission lens ratio of the focal length of the lens and aperture to measure, with F as the marker, each shot is marked with the F value, the amount of light and the F value is proportional to the square, smaller F value, then the larger the aperture. So we should choose to use aperture manual or auto iris lens light changes degree has been monitoring.
(3)Zoom lens (zoom lens)
Zoom lens with manual zoom lens and automatic telescopic lens two categories. Telescopic lens makes the lens focal length changes within a certain range in a single shot, it can make the monitored target zoom in or out, so it is often called the zoom lens. Typical optical amplifier specifications are 6 times (6.0~36mm, F1.2), 8 times (4.5~36mm, F1.6), 10 times (8.0~80mm, F1.2), 12 times (6.0~72mm, F1.2), 20 times (10~200mm, F1.2), grade, and the most widely used in electric telescopic lens. In order to increase the magnification, except the optical amplification may also impose electronic digital amplification.
In the electric telescopic lens, aperture adjustment has three kinds, namely: automatic aperture, DC drive automatic aperture, the aperture electric adjustment. The focus and zoom adjustment, only the electric adjustment and preset two, electric adjustment is driven by the motor in the lens, and the preset is to adjust the stop bit set in advance through the potentiometer inside the lens, which can avoid imaging process must be gradual adjustment, accurate and fast positioning. In the spherical cover integrated camera system, most of the telescopic lens preset positions.
Another interest users is fast focusing function, which is composed of focus measurement system and electric zoom feedback control system.
(4)Relationship between the lens and the camera the size of CCD
1/2 “lens can be used for the 1/2” 1/3 “can also be used for the camera, camera, but the perspective will reduce about 25%. 1/3 “lens is not used for 1/2” 1/3 “can only be used for the camera, camera.
(5)The scope of application of different types of lens
A、Application range of manual, automatic aperture lens
Manual iris lens is the most simple shot, applicable to illumination condition is relatively stable conditions, Manual Iris by several pieces of sheet metal. The luminous flux by a ring on the lens diameter adjustment. Rotating the ring can be close or open the aperture.
In the lighting conditions change in the environment or not used to monitor a fixed target, should use the auto iris lens, such as the current switch in the outdoor or artificial lighting, auto iris lens aperture movement is driven by the motor, the motor is controlled by the camera video signal.
Manual iris lens, auto iris lens and a fixed focal length (aperture) lens, auto iris lens and electric zoom lens division.
B、Fixed focus lens (aperture), general and electronic shutter camera supporting, suitable places for indoor monitoring of a fixed target.
Fixed focus lens is generally divided into telephoto lens, focal length lens with short focal length lens. In focal length lens focal length and image size is similar to the lens; focal length less than the image size is called the short shot, short focal length lens is also called the wide-angle lens, the focal length of the lens is usually 28mm below the lens, short focal length lens is mainly used for the environment in poor lighting conditions, where a wide monitoring range, focal length greater than that of said imaging size for telephoto lens, telephoto lens is also called a telephoto lens, the focal length of the lens is generally more than 150mm, is mainly used for monitoring the distant scenery.
C、Manual iris lens, can be matched with the electronic shutter camera, can be used in a variety of light.
D、Auto iris lens, (EF) can be used with any CCD camera support, can be used in a variety of light, especially for monitoring surface brightness changes, a wide range of places. In order to avoid halo artifacts and burn out the target surface, usually with auto iris lens.
E、Electric zoom lens, can be used with any CCD camera support, can be used in a variety of light, zoom lens is through the remote control device for optical focus, aperture opening, changing the focal length size
(6)The main performance index of the lens has the following:
A、Focal length: the focal length is determined by the size of field of view angle, focal length is small, large view angle, the observed was great, but the distance to the object resolution is not very clear; focal length numerical value, the field angle is small, the observation range small, as long as the choice of the appropriate focus, even far away objects can be clearly plainly. Because the focal distance and angle is one one correspondence, a determined focus means that a certain angle, so in the choice of the focal length of the lens, should be fully considered in detail is important, there are still a large range of observation, if you look at the details, on the choice of long focal length lens; if you look at the past from the scene, on the choice of the wide-angle lens small focal.
B、Diaphragm: the flux coefficient, denoted by F, measured by the ratio of the focal length of the lens aperture of F and D. Each lens are marked on the maximum F value, for example, 6mm/F1.4 represents the maximum aperture of 4.29 mm. The luminous flux and the F value is proportional to the square of the F value, the smaller, more luminous flux. The lens aperture exponential value is 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, the law is the exposure before a value is just a value corresponding to 2 times the amount of exposure. That is to say aperture lens are respectively 1/1.4, 1/2, 1/2.8, 1/4, 1/5.6, 1/8, 1/11, 1/16, 1/22, the former is a numerical NUMERICAL root 2 times, so the aperture index is smaller, the aperture is bigger, imaging target surface illumination is greater. In addition the aperture of the lens and manual (MANUAL IRIS) and automatic aperture (AUTO IRIS) branch. Used with the camera, Manual Iris for brightness is not the occasion, the amount of light regulated through the aperture ring on the lens of it, a one-time adjustment right now. Auto iris lens can be adjusted automatically along with the change of light, outdoor light, entrance for occasions such as large and frequent changes.
C、Auto iris lens: auto iris lens is divided into two categories: one category is called the video (VIDEO) driven, the lens itself contains the amplifier circuit, is used to control the camera video amplitude signal coming into the aperture motor. Another kind is called direct current (DC) driven, the utilization of the DC voltage on the camera to directly control the aperture. This lens contains only the galvanometer aperture motor, requires amplifier circuit camera. For all kinds of auto iris lens, usually have two adjustable knob, a ALC regulator (light regulation), with peak photometry and target light condition average two choices according to general average, metering gear; another is LEVEL (Ling Mindu), the output image becomes bright or dim.
D、Zoom: zoom into manual (MANUAL ZOOM LENS) and electric (AUTO ZOOM LENS) two, manual zoom lens is generally used instead of closed-circuit surveillance system of scientific research project. In the monitoring of large scene, the camera usually used with electric lens and a tripod head. Electric lens is good zoom range, can see a wide range of conditions, can also focus on a detail, coupled with the rotation can be up and down, the visible range is very large. Electric lens has 6 times, 10 times, 15 times, 20 times, if you know the benchmark rate, the focal length, we can determine the range of variable focal length of the lens. For example, a 6 times the benchmark electric lens, focal length of 8.5 mm, the zoom range is 8.5 to 51 mm continuous adjustable, viewing angle of 31.3 degrees to 5.5 degrees. The control voltage electric lens is DC 8V~16V, the maximum current is 30 ma. So in the controller, to fully consider the transmission cable length, if the distance is too far, voltage line production will lead to a decline in the lens cannot control, must improve the input control voltage or replace the video frequency matrix host computer with the decoder control.
(7)Focal length: 1 calculation formula calculation method: Calculation of field and focal length.
Field refers to the ingested object size, field size is the distance to the lens to be ingested objects, camera head and image size required to determine the.
A、the focal length of the lens, field size and the lens to calculate the distance of the uptake by the following object; f=wL/W 2, f=hL/h
f: the focal length of the lens
w: the image’s width (object imaging width in the CCD target surface)
W: object width
L: object to camera distance
h: image height (an image of an object in the CCD target surface height) field (uptake of scenes) height
H: object height
The CCD target surface size: unit mm specifications
The specification of 1/3 “1/2” 2/3 “1”
W 4.8 6.4 8.8 12.7
H 3.6 4.8 6.6 9.6
Because the camera screen width and height with the TV screen width and height, the ratio is 4:3, when the L invariant, H or W increases, f becomes smaller, when H or W unchanged, L increases, f increases.
B、Calculation of angle of view
If the horizontal or vertical angle can be calculated according to the formula of the width and height. Horizontal view angle β (horizontal viewing angle) β =2tg-1= vertical field of view angle Q (vertical viewing angle) q=2tg-1= type W, H, f. Horizontal view angle and the vertical angle of view as follows: q= or =q
Table 2 the value B the horizontal view of different sizes and different focal length camera layer when the f angle, if the horizontal or vertical angle can be calculated from the field angle can be calculated out of the field H and field width W. height
H=2Ltg, W=2Ltg
For example; the camera camera tube is 17mm (2/3in), the focal length of the lens f to 12mm, from table 2 check horizontal viewing angle of 40 DEG C and the lenses and ingested objects at a distance of 2m, find the field width W.
W=2Ltg=2 * 2tg=1.46m H=W= * 1.46=1.059m f more and long focal length, field of view angle is small, the goal of surveillance is small.
The graphic method
As previously shown, the camera field of view by the wide (W). High (H) and the distances from the camera (L) decision, once the decision to the camera to monitor the scene, the correct choice of the focal length of the lens on the origin of 3 factors;
*.To monitor the dimension of the object.
*.The camera and the object distance.
*.The camera device size: 1/3 “, 1/2” 2/3 “, or 1”
Graphic lens selection steps:
There is a simple relationship between field of view and the focal length of the lens required. Using this relation can choose appropriate lens.
Maximum width estimated or measured field; estimation or measurement camera and photographed the scene distance; use 1/3 “lens use figure 2, the use of 1/2 lens used in Figure 3, the use of 2/3” lens use figure 4, using a 1 lens use figure 5. Method: on the icon to W and L axes 2-5, find out the focal length of the lens should be used. To ensure that the object is completely contained in the field, should choose the coordinate intersection, numerical surface that line indicator.
For example: wide field of view 50m, distance of 40m, using the 1/3 “format of the lens, at the intersection graphs of 4mm lens than partial line a bit. This shows that if you use the 4mm lens can not cover the 50m field of view. And with a 2.8mm lens can completely cover the field.
F=vD/V or f=hD/H
Wherein, f represents the focal length, V represents the vertical CCD target surface height, V represents the observed object height, H represents the level of CCD target surface width, H represents the observed object width.
For example: if 1/2 “CCD camera observation, the object to be measured 440 mm wide, 330 mm high, lens focal distance of 2500 mm objects.
Can be calculated by formula:
Focal length f=6.4X2500/440 = 36 mm or 36 mm focal length is f=4.8X2500/330 when the focal length is numerical calculated, if there is no corresponding to the focal length of the lens is very normal, then according to the catalogue choice of similar models, the general selection value smaller than the calculation, this view will be greater.

6、Camera test steps
The test of main camera test sharpness and color, illumination, backlight compensation, followed by the spherical distortion, power consumption, minimum operating voltage, below the clarity and color and illumination measurement steps, backlight compensation first introduce.
(1)Definition: a multi camera measurement test, should use the same lens, (recommended to make a fixed focus, zoom lens, two) to test the card center circle appear on the monitor screen of the left and right side is accurate, clear and accurate number scale line has been given to the 10 groups of vertical lines and 10 horizontal lines group. Represent the vertical resolution and horizontal resolution, and a corresponding set of has given line number. Such as horizontal and vertical 350 LINE 800 line, it is best to use a black-and-white monitor. When the test can be in the far scenery can be focused, while measuring focus. Best can be both, can see the difference in the camera (to near convergence).
(2)Color reduction test: Test of the color monitor parameters should be selected. The first remote viewing figures, clothing, to see whether the color distortion, with contrasting bright, at the camera response sensitivity, with color pictures placed in front of the camera, look at the picture outline clear degree, too short or too thick, color object again respond to motion of the camera, to see whether the color smearing, delay, fuzzy etc.. Test conditions so camera most generation illumination should be measured in the 50+10V illumination conditions in the 50V, namely each camera the generation of illumination on the basis of ten volts, and the aperture should be kept close to the state.
(3)Illumination: the camera is placed in the dark room, anechoic chamber around the active 220V from incandescent lamps, a regulator, to adjust the brightness of high voltage Dailai regulating darkroom lamp voltage regulator, voltage from 0V to 250V. The indoor light is also available from the dark to the Ming Dynasty, when testing the camera aperture are open to the maximum when the record minimum illumination next value (the active light regulator dark to see not pure darkroom built-in screen) and the aperture to minimum and recorded the lowest illuminance next value, can also be the front and rear lights are voltage flash.
(4)Backlight compensation: there are two ways to test the parameters: one is in a dark room, the camera side pressure on the light, the light to, then placed a picture or text in below the light, the camera light camera, see the image and text can see picture, barbed not dazzling, and adjusting the AL, AX pull switch, see have no change, which had the best effect. Another is the camera to the window as in sunny conditions, you can see the image and text.
(5)Ball type distortion: watching the ball type distortion test card in the video camera at the front end of the sphere appears on the screen, see round has no elliptic, put the camera forward, look at the circle center has no amplification, and remote test edge, angle, frame has no radial distortion.
(6)Power consumption: the minimum operating voltage, using a multimeter to measure current, voltage regulator using small adjustment at

7、Installation and debugging the camera
Installation lens: C type and CS type two kinds, both threads are 1 inch 32 teeth, 1 inches in diameter, the difference is the distance from the target surface, different CCD lens, C mounting seat from the datum to the focus distance of 17.562 mm, than the CS distance CCD target face one more special loop length, CS distance focal distance of 12.5 mm. Don’t look down on this a connecting ring, without it, the lens and camera can not normally focus, image blur. So in the installed in front of the camera, take a look at the camera and lens is it right? The same interface mode, if not, we need to increase or decrease according to specific circumstances connected with the ring. Some cameras don’t have to pick up the ring, while the afterimage adjusting ring (such as Panasonic products), regulation, use a screwdriver to loosen the adjustment ring screw, turn the ring, the CCD target surface relative to the mounting base will be back (front) movement, also play a connecting ring effect. In addition (such as SONY, JVC) in a manner similar after adjusting ring, screw it in the camera side, unscrew rear, a top gear adjustment, also can make the image clear without addition and subtraction connecting ring.
ON/OFF (automatic gain control): the camera with a signal from CCD amplification to use video amplifier level, which is equivalent to the amount of gain, higher sensitivity, but in the light environment amplifier overload, the video signal distortion. When the switch is in the ON, fully open the lens aperture in low light conditions, automatically increase the gain to obtain a clear image. The switch in the OFF, natural and low noise of the image in low light.
ON/OFF (auto white balance): switch to the ON, through the lens to detect the characteristics of the light source / color, thus continuously and automatically set the white level, even if the property / color temperature change can also control the red and blue signal gain.
ALC/ELC (automatic brightness control / electronic brightness control): when choosing a ELC, electronic shutter according to the incoming light brightness and continuously and automatically change the exposure time of CCD image sensor (from 1/50 to 1/10000 seconds continuous regulation). This way, we can use fixed or manual iris lens instead of ALC auto iris lens.
Note: outdoors or in bright environment, because the ELC control is limited, should choose ALC lens; in some unique lighting conditions, may be any of the following circumstances:
①In the spotlight or windows high brightness objects with strong tailing or fuzzy phenomenon
②Image and color reproducibility was flashing instability
③White balance with periodic change, if the occurrence of these phenomena, should use the ALC lens.
With fixed iris lens using ELC mode, the image depth may be less than the use of ALC type lens the depth of field. Therefore, the camera in the open fixed iris lens completely using ELC mode, the depth of field than the ALC lens is small, but the image of distant objects may not be in focus.
When the lens is auto iris lens, will need to switch to ALC mode.
BLC ON/OFF (backlight compensation switch)
When the background lighting powerful and useless affect central important object definition, should put the switch to the ON position.
①when the Haeundae and matched or lighting change rapidly, suggested that the switch is in the OFF position, because in the ON position, the lens aperture is slow;
②If the object is not in the image center, backlight compensation may not give full play to the role of.
LL/INT (synchronized switch)
This switch is used to select the camera synchronization mode, INT as the internal synchronous 2:1 interlaced synchronization; LL power synchronization. Some cameras and a LLPHASE power supply synchronous phase controller, when the camera is used in a power synchronization status, this device can adjust the phase video output signal, the adjustment range is probably a frame. (adjustment needs professional personnel)
VIDEO/DC (camera control signal selection switch)
The control signals ALC auto iris lens is two, when the need will auto iris lens DC control signal is arranged on the camera when, should choose DC position; need auto iris lens mounted video control signal, should choose the location of the VIDEO.
When choosing the ALC auto iris lens video driver, there will be a video level control (VIDEO LEVEL L/H) may need to be adjusted, control level of the controller output to the auto iris lens, is used to control the aperture of the lens opening and reduced (or light).
In the camera accessories, a small plug of a black, four pin plug, socket connected with a camera on the black. If the auto iris lens driven by DC, the lens is ready to plug, as long as is inserted in the socket, the selection switch to DC; if the auto iris lens with the video driver, user needs according to the instructions on the label, with a soldering iron. Because manufacturers definition is different, so the welding method also has difference, attention please install.
SOFT/SHARP (level of detail selection switch)
The switch to regulate the output image is clear (SHARP) or smooth (SOFT), usually to factory setting, s in the SHARP position.
FLICKERLESS (no flashing mode)
In the power supply frequency of 50Hz area, CCD accumulation time is 1/50 seconds, if you use the NTSC camcorder, the vertical synchronization frequency is 60Hz, this will cause visual image is not synchronous, appear on the monitor flashing; otherwise, PAL camcorder in power for the 60Hz area will also have this phenomenon. To overcome this phenomenon, in the electronic shutter set no flashing mode file, the NTSC format camera provides 1/100 seconds, providing a fixed shutter speed of 1/120 sec of PAL camcorder, can prevent the image monitor flicker. Manual electronic shutter: some users use CCD uptake velocity faster object, if taken with 1/50 seconds, will produce the tailing phenomenon, serious impact on image quality. Some camera gives manual electronic shutter, the charge coupled CCD speed fixed at a value, such as 1/500, 1/1000, 1/2000 second, the charge coupled CCD speed increase, so the captured image will have less tailing phenomenon, but also for the observation of a high-speed moving or electric spark of a class of objects, you must use the set. So, some special camera provides manual electronic shutter, provided to the special user. Manual electronic shutter adjustments need to refer to the random instructions, will not repeat them here.
Add that:
There are a lot of user requirements with no light environment in the evening under control, please note: due to the CCD camera also relies on light reflection to imaging, if there is no light, the image will only be dark with a lot of snow. How to get the picture? A method is visible light, such as street lights, searchlights; one is combined with infrared light (especially requirements cannot install visible light occasions), for color CCD camera, not in response to infrared light, some day and night color camera at night will automatically turn into black and white pattern. So, monitoring system to your request to use at night, must use the monochrome CCD camera.
Infrared light is indoor, outdoor, short distance and long distance, commonly used indoor 10~20 meters range of infrared light, due to the wall reflection, the image effect is good; in the room of long distance infrared light effect is not very ideal, but the price is expensive, not necessary generally not used.

Part 2   Spherical Yuntai
With the rapid development of television industry, the technology has improved a lot of make a spurt of progress. Spherical PTZ cameras developed in recent years (the ball) is the outstanding representative of. The ball machine with its beautiful appearance, hidden, personalized, convenient installation, is gradually replacing traditional tripod head protective cover, but in view of the feature of ball machine itself, we should have a deep understanding, to pay attention to the selection, configuration, reasonable, scientific use in engineering.

1、The ball machine classification and structure
Generally speaking, the ball machine functions are divided into ordinary ball machine and high speed preset ball machine. Here, we mainly discuss the ordinary ball machine. Ordinary ball machine mainly refers to the head in the ball machine for ordinary Yuntai or no built-in yuntai.

2、The main factors influencing the ball Yuntai performance and Countermeasures
As the ball machine technology, factors affecting the ball machine performance and quality are in many aspects, but mainly from the following aspects:
Transparent ball cover (or spherical)
(1) the main reason image sharpness drop:
•Spherical material
•Spherical surface, , finish
•The manufacturing process of spherical solution:
The optical acrylic material, its light transmittance
②Surface smoothness high, can not have any defects, including: rough, uneven, scratches, , bubbles.
③Spherical sophisticated manufacturing processes, strict control of the time, temperature and so on, in addition, job site clean, neat, clean is an important control factors.
(2) image ghosting a this failure is most often the user and engineering business, failure is not easy to find the
The main reason: (see figure B)
Schematic diagram of B image ghosting reason
•Spherical curvature, for example: 9 “14” ghost opportunity
•Spherical δ is too large
•Spherical parts uneven
•The lens of the ball cover size mismatch
Analysis of the causes of:
Because the camera imaging is generally a pixelated, these reasons can lead to imaging artifacts (see figure B)
The solution:
①Large multiple lens to use large size ball machine
②Try to use Delta small spherical
③The delta to similar sphere, spherical and uniform thickness as consistent as possible
④According to the lens multiples, rational purchase ball machine size.
(3) light transmittance decreased
The main reason: spherical color
Because one of the advantages of ball machine is hidden, so the concealment stronger requires the ball cover the deeper the color. From this dark sphere negative effect is the light transmittance decreased.
The solution:
①According to the scene illumination, choose spherical color
②Try to choose a low illumination camera
③Reasonable selection of spherical color, generally used in shallow, light blue smoke, can compromise to solve this contradiction.
(4) reflective
The main reason:
•The ball machine internal reflector.
•The camera and the spherical distance too far.
•The rotation angle and external light source optical multi angle reflection.
The solution:
①The ball machine to reduce the reflective material
②As the camera installation and spherical close
③Try to avoid the ball machine and external light unreasonable reflection position

3、The ball machine structure
Generally speaking, in the camera fault for outdoor use significantly more than the indoor use, the main reason is because of the outdoor camera protective equipment problems, and it is the protection problem greatly reduce the service life and reliability of the cameras and lenses work. So the structure design of science is also an important index ball machine performance.
(1) outdoor type – temperature, rain, heating defrosting are three major difficulties
High temperature
The outdoor temperature is mainly direct sunlight. General ball machine in the outdoor sunlight, internal can reach 55 ℃ -60 ℃. General protective cover can be made of the internal cooling way down, but the air condition is the convection, and the ball machine without convection channels, so the ball machine optimal cooling means is the sun. Design of advanced ball machine adopts a double-layer structure design, as shown in figure A. Double convection ventilation design is the best means of effective cooling. In general, the ball machine double sunshade cover can reduce the internal temperature of 3 ℃ -5 ℃ ball machine, the single top cover, the material is also very important, usually aluminum top cover insulating effect is the worst, engineering, ABS, and DMC, fiberglass insulation effect is obviously superior to the material.
Waterproof and seal
Excellent sealing ball machine requires a lot of rain and. The rain should not only consider the rainfall, but also to consider the direction. There is typhoon in coastal area in China often, the rain is full, thus sealing the high ball machine. Generally speaking, leaking water mainly from several aspects:
•The ball machine itself poor assembly
•Spherical and top cover contact part not sealed or not sealed
•The ball machine rack inlet
•The installation process is not in accordance with the instruction do waterproof processing in key parts (such as support and the ball joint, support and wall junction etc.)
•Install ball machine line processing is not good, the water along the wire into the ball machine, pay attention to the above points can greatly reduce water leakage may.
Heating and defrosting
Due to the camera and lens ball machine were lower in the ball inside the machine, so the heating function design of ball machine to be very reasonable. Generally speaking, the heater is installed on the upper part of the ball machine, and shall be equipped with synchronous small fan, the heat is blown to the lower part and spherical ball machine, in order to play the role of heating camera lens and defrosting effect.
At present, the new design is the medial wall heater installed in the ball machine, at the same time synchronized with fan. Its advantages are shown in figure C. The heated air circulation in the science of ball machine, no hot air choke and dead zone, maximize the uniform heating, the heating, defrosting, except for the purpose of water vapor.
Figure C sidewall heating and the heat cycle design of fan
(2) motor and internal structure design
•The motor is the key component in head and ball machine. Generally speaking, the current domestic and foreign motor technology the main index to judge the reliability of the motor is good. Therefore, the motor running hours at a certain temperature, humidity conditions is hard index. In addition, motor disorder, stuck, stop, heat, noise, interference and also is an important index of tilt motor, selection of fine motor can greatly improve the life and reliability of the ball machine.
•Scientific, practical internal structure design. Such as: camera plate can be adjusted up and down, as mentioned above, can maximize the camera to the ball cover; internal alignment reasonable; has convenient installation and wiring; head small hysteresis; continuous rotation speed jitter is reduced; the design is reasonable, and also an important index.

4、And the prospect of development trend of ball machine
At present foreign ball machine development trend as a hand:
(1) the ball machine appearance and installation site environment, harmonious, beautiful
(2) the camera lens, miniaturization and integration trend, the ball machine also miniaturization
(3) the fundamental solution to the contradiction of concealment and low in light transmittance, is a fundamental revolution ball machine development
(4) the development of preset ball transmission
In short, the ball machine development is in the replace traditional head protective cover, and some conditions are in high-speed ball machine to replace the preset position, but in any case, ordinary ball machine to its low price, strong applicability (without communication protocol), by the majority of users favor convenient installation and debugging.

Part 3  Cloud platform
The head is supporting equipment installation, fixed camera, it is divided into fixed and electrically operated rapes two.
The fixed platform is applicable to the monitoring range is small, good camera mounted on the fixed platform can adjust the camera level and pitch angle, reach the best working attitude as long as the adjustment mechanism can lock.
Electric PTZ is suitable for scanning and monitoring of large scale, it can enlarge the coverage of surveillance cameras. High speed electric head posture is composed of two executive motor to achieve, motor receives the signal from the controller to accurately positioning. In the control signal, the video camera can automatically scan the surveillance area, can also be on duty under the manipulation of tracking and monitoring object in the monitoring center.
Yuntai divided only about the level rotary head rotation and can rotate around can also on full tilt rotation according to the characteristics of the rotary can. In general, horizontal rotation angle is 0 ° ~ 350 °, vertical rotation angle is +90 degrees. Constant horizontal rotating speed PTZ is generally 3 ° ~ 10 ° /s, the vertical velocity of about 4 ° /s. Horizontal rotary speed transmission platform is generally 0 ° ~ 32 ° /s, vertical rotation speed in 0 ° ~ 16 ° /s. In the high-speed camera system, horizontal rotating speed head up to above 480 ° /s, vertical rotation speed above 120 ° /s.

Part 4   Protection cover
The protective cover is an important component in monitoring system. It is the protective device of the camera in the normal use of the dust, rain, high temperature conditions.
The protective cover is generally divided into two categories. One is the protective cover for indoor, the protective cover has the advantages of simple structure, low price. Its main function is to prevent camera ash and safety protection effects, such as anti-theft, anti sabotage. Another kind is the protective cover for outdoor, the protective cover for all-weather protective cover, regardless of wind, rain, snow, high temperature, low temperature and other harsh conditions, can make the installation in the protective cover of camera work. The protective cover with cooling, heating, rain, snow and other functions. At the same time, in the rain and snow weather can still make the camera captured image in normal, all-weather protection cover glass window is equipped with controllable wiper.
At present, all-weather protection cover is better by using the semiconductor device heating and cooling shield. The protective cover is provided with a semiconductor element, can automatic heating, can also be automatic cooling, and less power consumption. In addition, there are hemispheric, spherical protective cover, the protective cover is equipped with a universal adjustable bracket, modelling is beautiful.
Protective cover selection
The protective cover is divided into indoor and outdoor two. Indoor protective cover is mainly dust, some also have hidden action, make monitoring places and objects that are not easily detectable by monitoring. There are sunscreen, waterproof, dustproof, anti freezing and anti condensation effect outdoor shield function. General outdoor protection cover is equipped with a temperature relay, automatic open fan cooling in high temperature, automatic heating at low temperature. When it rains, can be manually controlled rain wiper brush. Some outdoor shield glass can also be heated, when the frost protection cover, can be heated defrosting.
Note monitoring equipment maintenance
1、The power supply socket for each camera should always check, prevent the plug off.
2、To ensure power supply voltage for each camera and the monitoring center is relatively constant.
3、The camera to the low position as a clear sign of non management personnel to touch, to remind.
4、Monitoring Center for monitoring and control equipment sent special requirements, non monitoring personnel are prohibited from operating.
5、The monitoring center in every night in no circumstances must be on the monitoring equipment outages.
6、The monitoring equipment often clean the maintenance

High-definition network camera technology development trend

In recent years, high-definition video surveillance technology gradually into people’s eyes, become the future direction of the security monitoring technology development. More and more manufacturers began to launch high-definition products. Among them, as HD video surveillance of the “pacesetter” — high-definition network camera, but also by the vast number of manufacturers of all ages, all kinds of products emerge in an endless stream, every kind of technical terms is also allow the user to see things in a blur. How to grasp the pulse of high-definition network camera, understanding its future development direction? In this paper, starting from the view of technology development, is introduced briefly the development trend of high-definition network camera.
1、The improved resolution
High definition, originated in the field of digital television. High definition television, also called “HDTV”, is determined by the American Society of motion picture and television engineer HDTV standard format. Television clarity, is the horizontal scanning line number as a measure, it will be divided into: Hd 720p format (750 vertical scanning lines, 720 visible vertical scanning lines, 16:9, resolution of 1280 × 720, line /60Hz, line 45KHz), 1080i format (1125 vertical scanning lines, 1080 visible the vertical scanning lines, 16:9, resolution of 1920 × 1080, interlaced /60Hz, line 33.75KHz) and 1080p format (1125 vertical scanning lines, 1080 visible vertical scanning lines, 16:9, resolution of 1920 × 1080, progressive type).
To monitor the industry reference standard of radio and television industry. Shanghai city has the first domestic digital camera for security monitoring with local technical specifications in 2010 September, according to the definition, standard digital camera from low to high A, B, C level three. Among them, the B level resolution ≥ 1280 × 720, C level resolution ≥ 1920 × 1080. Visible, 720p and 1080p has become an industry standard high-definition network camera.
However, some manufacturers for high-definition network camera also has other names, such as megapixels high-definition network camera, two million pixel HD network camera and so on, which can be interpreted named “non standard”, there is a relationship between it and the “standard”, but not simple correspondence. For example, 720p for 921600 pixels, 1080p pixels of 2073600, can be called a pixel and the two million pixel, but 1300000 pixels often see the actual resolution is 1280 * 1024, although also has a higher resolution, but does not accord with the radio and television industry standard.
On the resolution, the development of high-definition network camera can be said to be a thousand li a day, in addition to our current contact more million pixels, 1300000 pixels, 2000000 pixels, 3000000 pixels, 5000000 pixels, 8000000 pixels of products have appeared on the market, or even tens of millions and tens of millions more pixels of products also began in the surveillance industry emerged. Can say, people in the pursuit of more clearly see the road will never stop.

2、COMS substituted for CCD
The photosensitive device is part of the camera is the core, CCD is mainly adopted at present (Charge Coupled Device, charge coupled device) and CMOS (Complementary Metal-Oxide Semiconductor, complementary metal oxide semiconductor) two. Both by the photosensitive diode (photodiode) for photoelectric conversion, the image is converted into digital signal, but the main difference is the digital signal transmission in different ways. CCD not distortion in data transmission, so each pixel data can be collected to the edge and then amplifying and processing; and CMOS process will produce noise in the data transmission distance is longer, therefore, must first be amplified, then each pixel data integration. Also because of the different data transmission mode, CCD and CMOS sensor also has many differences in effectiveness and application. Generally think of CCD sensor has better sensitivity, resolution, noise control, CMOS sensor, CMOS sensor has the advantages of low cost, low power consumption, and highly integrated features.
Aiming at the shortcomings of CMOS performance, the industry is to be improved through continuous technological innovation, one of the most important technical breakthrough in the imaging performance under low illumination and reduce the noise signal in the image.
In order to improve the performance of low illumination, the proposed micro lens (Micro Lens) technology, so that more light can be imported into the surface of the CMOS sensor (photodiode), thereby increasing the induction of brightness, but the micro lens technology has belongs to micro electromechanical systems (MEMS) level, rather than the original semiconductor circuit level the challenge, so the increase is not difficult to imagine.
To reduce the noise signal in the image, a method of the original semiconductor process is improved, the CMOS circuit on the silicon surface doping, thus forming a pinning layer (Pinning Layer), the structure can be absorbed into the internal source of silicon wafer, thereby reducing (light electricity diode) surface noise, this method is also known as the photoelectric diode (Pinned Photodiode). At present, this approach does improve the problem of noise, so that the image quality, but at this stage of the process will also increase the manufacturing cost of wafer.
With the development of technology, the performance of CMOS is improved rapidly. In addition, although the same size of CCD sensor resolution is better than CMOS sensor, but if we do not consider the size limit, CMOS can effectively overcome the difficulties of large size of photosensitive original manufacturing advantage on yield of CMOS, so at much higher resolution will be an advantage. In addition, the response speed of the CMOS is faster than CCD, therefore more suitable for large data quantity characteristics of HD monitor.
From the market point of view, the traditional manufacturer CCD SONY has begun to shift to CMOS, not only to develop the ClearVid CMOS, launched a HD CMOS Exmor series product, in the production of high-definition network camera is almost uniform in the CMOS sensor, which can be regarded as a stage victory for CMOS sensor.

3、ISP (Image Signal Processing) is encoded chip integration
To achieve good image quality, in addition to the handling of light front lens, sensor, image processing part is high-definition network camera can not be ignored in a ring. Typically, the sensor part is provided with a built-in image processing chip to deal with some simple functions, and automatic exposure, more complex automatic white balance correction and auto focusing function must pass the back-end ISP processing, in order to get good imaging quality.
The traditional ISP is realized by the special ASIC or DSP, with the development of technology, code chip back has been more and more ISP function will be to integration.
On the TI DM36x platform as an example, the video processing subsystem (VPSS) containing CCD or CMOS controller, directly from the original video signal, and then preprocessed by integration of the ISP, including H3A treatment (i.e., automatic exposure (AE), automatic white balance (AWB), automatic focusing (AF)), lens deformity correction model (LDC) processing, hardware face detection engine, the image processor (IMCOP), image processing accelerator (IPIPE), and enhanced on-screen display (OSD) etc..
Through the integration of ISP, can not only greatly reduce the cost of the system, the more can greatly enhance the stability of performance optimization of video, image in optical field. The imaging quality high-definition network camera and its important role.

4、Intelligent analysis function more practical
Intelligent is the inevitable trend of development of monitor system, its essence is from analog or digital video automatic tracking and identification of objects, motion analysis and extract useful video information. The network video surveillance, intelligent front-end camera has the extremely important practical value. For example, the abnormal alarm record, is the video image monitoring, through the analysis of recognition front-end intelligent network camera, will only have abnormal image transmission to the rear to record and display, which can greatly reduce the burden on the network, effectively save bandwidth resources. On the other hand, intelligent video surveillance system in the intelligent network camera back-end, just focus on the management of the target data information sent from the front end of the camera, without the need for processing and recognition of video signal, so the back-end system does not need the equipment can complete intelligent video analysis is expensive. Because the front back only to send the pre / alarm event related picture display, the monitoring center staff can easily complete the entire surveillance system. This video features, also make the video search and playback becomes simple and rapid, thereby saving valuable time.
In recent years, video surveillance industry for many intelligent analysis scheme is extended, but the effect is not good, often just marketing gimmicks. The reason, on the one hand is the intelligent analysis algorithm itself technology is not perfect, no real sense of the breakthrough; on the other hand is the traditional “SD” camera resolution is limited, can not provide sufficiently clear image for the intelligent analysis algorithm. With the wide application of high-definition network camera, this situation will be changed.
At present, the high-definition network camera has been realized or intelligence is implemented analysis functions: Video occlusion detection, video change detection, video fuzzy detection, video motion detection, in the entrance of statistics, population movement and congestion identification, left recognition, intrusion recognition and video loss etc.. These functions look over the intelligent analysis function to “inferior” much, but more practical.

Unlike the analog video monitoring system closed, between products and products of network video monitoring system to achieve the system compatibility has become a serious problem, put in practice the standard problem, discussion about increasing, about security product interoperability standards organization have been incessantly, where ONVIF, PSIA two standards organization the effect of security enterprises more and more.
ONVIF, full name Open Network Video Interface Forum, namely the open network video interface forum, jointly launched by the Axis, Bosch and Sony three companies, is the world’s largest influence network video surveillance industry standards organization, its purpose is for common fixed open network video surveillance industry standards to open, open principle. In 2008 November, the Group officially launched the ONVIF edition standard — ONVIF core specification 1. This standard will define generic protocol exchange between network video device information (such as device search, real-time video, audio, data and control information).
PSIA: (Physical Security Interoperability Alliance) interworking entity security alliance, founded in 2008 August. The aim is to create a standard for physical security system hardware and software platform. The alliance is committed to make different security system based on IP network compatibility. PSIA also have Cisco, GE, Honeywell and Panasonic and other major brands, the members in the network camera market share slightly inferior.
At present, the number of firms and the influence of support, the ONVIF alliance. According to IMS Research, the ONVIF members to occupy the market share of 72%, have been a large number of member companies in North America, Europe and asia. In addition to the three founding companies outside the company, Canon, Panasonic, Samsung, TI, Hikvision, Cisco, Siemens, Zhejiang Dahua, GE, MARCH, IDIS, CNB, IndigoVision, American Dynamics, Anixter, Axxonsoft, Dallmeier, Deister, Genetec, HiTRON, Honeywell, ITRI, Itx, Milestone, NICE, Optelecom-nkf, Pacom, Pelco ZTE, Pravis, and other influential enterprises are involved in this standard organization. As of 2010 May, ONVIF has more than 150 members.
Of course, whether it is ONVIF or PSIA, are formed the enterprise spontaneous organization standards, but the response was more and more enterprises, still has a very important significance.
The next few years, the construction cost of network video monitoring system will be reduced rapidly, the market share will also get very big promotion, in the face of increasingly large market, the video surveillance industry chain division of labor will be more and more detailed. The maturity of the video surveillance market will be formed industry cooperation pattern closely, which makes the manufacturers products to supply standardized interfaces, in order to meet the benign development of the whole monitoring industry. In this sense, the standard will be high-definition network camera to the pass of the market.

6、To further improve the transmission technology
High-definition network camera in give people a clear visual experience at the same time, also put forward higher requirements on the network bandwidth. The 720P real-time video as an example, high-definition network camera uses standard H.264Main Profile compression algorithm requires at least 2Mbps can obtain the “HD” visual effects, while the 1080P real-time video should be more than 4Mbsp. Uplink bandwidth has been unable to meet the needs of ordinary ADSL HD video. With the maturity and application of 3G, Wi-Fi, network, wireless, wired broadband technology, remote transmission of the large flow of data transmission more convenient, it also cleared the obstacles of high-definition network camera in a broad range of applications.
At present, in peace, city financial network monitoring project built fiber optic network or local network is usually realized by 1000M network. The Gigabit bandwidth, mounted on the front 100 1080P real-time high-definition network camera (even by each resource 4Mbps calculation), occupy the total bandwidth of less than 50%; if it is transmitted by 720P, bandwidth can also be reduced by half. In this way, can apply effective support high definition network camera.
Wireless transmission, 3G network has accelerated the speed of the Internet to mobile phone, video phone, mobile phone game applications like a raging fire. But in the video surveillance industry, yet no substantive applications. Investigate its reason, one is 3G network construction is lagging behind; the two is the 3G price is still too high. In the face of HD video surveillance for the bandwidth requirement, 3G is inadequate. If we really want to achieve high-definition wireless video surveillance, also need to wait for the promotion of 4G. At present, the emergence of TD-LTE, open the 4G era HD video monitoring front door for us.
TD-LTE is TD-SCDMA to IMT-Advanced (4G standard) evolution direction and work foundation, is the inheritance and development of the Chinese independent intellectual property rights of the TD-SCDMA technology, and has broad international support. According to the TR25.913 definition of 3GPP, rate of LTE peak demand is very high, 50Mbps uplink, downlink 100Mbps. From the perspective of spectrum efficiency, spectral efficiency both uplink also is down, is 3-4 times the current network. The development of LTE technology has attracted the participation of different system, including UMTS (3GSM), and CDMA2000 camp participation, make LTE become a possible future wireless network 4G.
At the Shanghai World Expo, China Mobile to build the TD-LTE demonstration network covering 5.28 square kilometers, Expo Park, TD-LTE outdoor station 17 to build, the venue of the 9 indoor coverage, including Pudong 7 venues, Puxi 2 venues. Mobile high definition conference, TD-LTE demonstration network video monitoring, mobile HD video mobile HD VOD transmission, portable videotext and so demonstrate business are open to the public on the basis of, and achieved good results.

With the continuous improvement and development of the monitoring technology, high-definition network camera as one of the main direction of control technology, combined with the optical imaging technology, intelligent analysis technology, network transmission technology bring new change, continue to meet the demand of market competition at the same time, tending toward a perfect self realization. It has a profound impact on the field monitoring, will profoundly change the way we live.

The three core problems in the development of HD monitor

HD megapixels network camera is a professional video surveillance camera security industry application launch in monitoring field. In the HD era, network camera HD technology determines the direction of its development. High-definition network camera so that the image clarity has been a qualitative leap, but also brought a series of realistic problems for HD monitoring system.

1、The problem of bandwidth
Due to the limited network bandwidth, high bit rate video has become the biggest bottleneck in the application. How to use bit rate transmission may lower the quality of the video is the first problem need to be solved as soon as possible HD monitor. At the same time due to network heterogeneity, different networks have different channel characteristics, different users to enjoy the network bandwidth is not the same, even the same user bandwidth may be subject to change. With the development of monitoring and control field, a variety of user terminal has the need to connect the video, such as LAN monitoring network bandwidth is more ideal, users want to browse for a high quality video; and the mobile phone monitoring field due to the limited bandwidth, the user is more important in low bit rate video stream fluency. How to adapt to these different bandwidth environment is the need to address the problem of HD monitoring equipment

2、Display problem
Compared with the standard definition video, information content of HD video is enriched, corresponding to the decoding display performance is greatly improved, such as the current mainstream PC machine can easily achieve 8 D1 decoding video display, but if the front end is 1080P HD video, barely decoding display 1. For large video monitoring platform, if all of the use of HD video decoding, the server will be great pressure.

3、Storage problem
Image resolution enhancement, will consume much more storage space. In 1920 × 1080@30 frames of video as an example, using the H264 encoding algorithm, in order to ensure clarity, stream should be maintained at more than 6Mbps, about 4-8 times of standard definition video. In standard definition video condition, a 16 DVR built-in 8 2T hard disk can meet the long time video storage requirements, and in HD monitor, this time will be greatly reduced, which will bring about an increase in storage costs.

Analysis of high definition IP camera market

Today, IP application trend of penetration, in various fields has be a trend which cannot be halted, how to grasp the development trend of introducing IP, HD monitor, gradually become the camera manufacturers, integrators and owners to focus. This paper discusses the analysis, IP HD monitoring technology in engineering practice and the existing problems, hoping to find some inspiration and reference for all levels of security practitioners play.
“Standard” design of video monitor system in engineering GB50395-2007 of digital IP control system has made the definition ( mode), “analog camera increase digital coding function, called the network camera, digital video and can also be other digital camera. Digital switching network is Ethernet and DDN, SDH transmission network. Digital coding device can use DVR or video server with recording function, treatment, control and record the measures of digital video can be implemented in any part of the front, transmission and display”

Can see from the front end to the transmission, storage, control have been realized, from the point of view of the engineering application, the digital are in IP based on the realization of the. In this architecture, we introduce IP HD video camera on the front end, has formed a complete set with IP HD monitor system of national standards.

2、Digital IP monitor benefits
(1)IP monitoring system has the advantage of full digital, can the introduction of high-definition video technology and convenient, only need to replace the front camera.
(2)The front-end IP monitoring system can also use analog camera DVS (video encoder) form access system, for love simulation machine user, still retain a choice.
(3)At present, the IP monitoring system is the only way to achieve HD monitoring system architecture. Monitoring high-definition cameras, must be compressed using code, cannot use the source current output (HD-SDI, HDMI, DVI, YPrPb color difference), monitoring system cannot handle and transport is not compressed Gbps level data flow. If the IP monitoring system without HD video camera, video effects, management function and the analog camera current + DVR ( model basic indifference, even the convenience in use and control is less than the latter.
(4)The special requirements of the user, do intelligent video analysis can be monitored in IP platform.

3、Scale advantages and disadvantages of Qing and HD
The paper SD, HD is a high-definition television industry classification is introduced, the theoretical resolution of subscript clear PAL 625 line, to blanking, the theoretical value is 575 line. But HD, refers to 720p or more than 1080i resolution, from my personal point of view, HD entry resolution is 1920 * 1080p and 1600 * 1200p. The simulation is divided into SD and IP SD, HD all camera IP.
3.1Mark defect cleaning system
(1)Monitoring the panoramic view, there is no details;
(2)Push in, amplifying a local, it missed out on the global monitoring and recording;
(3)To go to a certain point of view, it missed out on other range of monitoring and recording;
(4)Simulation system for video analysis is relatively difficult, high cost;
3.2HD system advantage
(1)Panoramic + details at the same time monitoring
(2)High definition (minimum of 1920 × 1080p and 1600 × 12,, 00P) to see clearly, not only the macro record clear, and clear the microscopic details, can be used as evidence
(3)When there is no leakage, no entry ‘don’t see’ (relative to the standard blind spot cleaning ball machine)
(4)A high-definition camera can be worth much mark clear camera view and pixel, from a specific project engineering point of view, such as the use of HD machine can reduce the number of camera calibration clear, cost lower.
3.3The SD and HD contrast
Comparison of pixels.

Video camera



SD camera







Zhun Gaoqing camera

HD ready





HD camera










As can be seen, the camera HD entry-level model 2000000 pixel, the pixel that is equivalent to the 4CIF standard machine 5 times, an equivalent to the 5. But HD machine 5000000 pixels is equivalent to 10 4CIF SD camcorders.
Compared with the actual image.

HD image                                                    Standard image

The local amplification, shot in HD since pixel rich picture object, characteristics of human body, still visible, can be a powerful evidence information.

4、Design and practice of IP HD system
Below we combining with an actual engineering case, to discuss the design idea of IP HD monitoring system, and the equipment selection principle.
A beverage production enterprises as an example, the factory has 5 workshops, because of their need for production process monitoring and production process for the public transparent and open, to build a set of IP monitoring system. Each workshop about installation of 50 sets of IP HD video camera for monitoring of the production line, workshop periphery channel, corridor, dynamic, distribution, installation of 30 sets of IP SD camcorders, each workshop on the spot to set up a sub control center. The factory set up a total control center.
4.1Front end choice
The workshop area is very large, the production line is very long, to achieve a comprehensive monitoring of pipeline, the SD camcorders words, need to install the number can be more comprehensive coverage, the high-definition camera, measured by the need to install 50 party can meet the requirements of. And in the lighting shop is good, a COMS camera, can get very good picture quality. Monitor industry mainly convective line of finished and semi-finished products, prevent the products in the pipeline on the track jumping and shaking down, but also to prevent staff “inside job”, so the demand for real-time monitoring picture is very high. According to the site conditions and requirements, we decided to use 2000000 pixels of 1920 x 1080p IP camera, its main performance index and the reasons to choose to:
Resolution: 1920 x 1080, 16:9 broadband, can provide a more broad than the 4:3 picture, suitable for long pipeline monitoring, reduce the number of cameras.
Frame rate: 1920 × 1080p at up to 25 frames / second, guarantee the real-time and continuity, can fully monitor the dynamic situations of pipeline.
Compression method: use H.264 compression technology, reach the average rate of 2 ~ 4Mbps in 1920 * 1080p@25fps; the lower stream, can reduce the storage capacity requirements, reduce the cost, improve the economy.
Lens: the lens special selection of 3000000 pixels, 3 ~ 8mm manual zoom, automatic aperture. The 3000000 pixel camera with higher resolution than ordinary megapixel lens, the camera is more suitable for 2000000 pixels; 3 ~ 8mm manual zoom lens, can according to the actual situation, the flexible adjustment of the focal length of the lens, the camera better and pipeline site match.
Transmission interface: RJ45100M ethernet.
Power supply: IP HD video camera can also through the Ethernet POE power supply, connect the cable to all, as long as a super 5 4 to UTP. Considering the POE power supply switch cost is relatively high, in order to reduce the cost, using a separate power line 12V DC centralized power supply. Because of the POE power supply is the icing on the cake, we use separate power supply for the practical application of the camera does not have any effect, and the use of low voltage power line with UTP Cable Co pipe laying, without a separate laying pipeline.
Workshop periphery channel, corridor, power distribution room, among others such as, for monitoring scenario is, requirements are not very high, the conventional IP SD camcorders. IP SD camcorders very mature technology, selection and allocation principle in this no longer tired.
4.2Transmission network
IP video occupied the larger flow, monitoring system separate the construction of a set of dedicated network system, not in combination with other production, business network, so as not to affect each other, the network dedicated. We first analyze the Ethernet port equipment used in the system speed, then according to the demand of the equipment on the rate, the corresponding switch port configuration.
IP HD (SD) camera: 1 100M ports each, a total of 50 + 30 = 80, 80 ports;
DVS (video encoder): 1 100M ports each, no;
The video server (video stream forwarding and management): 1 1000M ports each, a total of 2 port;
Storage equipment: 4 1000M ports of each of 2 ~, at 2 I, a total of 2 units, a total of 4 port
TV wall display workstation: 1 1000M ports each, each separate output the 4 picture, a total of 4 workstations, can output 16 pictures, 4 port;
Management station: 1 1000M ports per set, 2 sets, a total of 2 port;
As can be seen in addition to front-end using fast, the backstage management and storage are using Gigabit port.
IP DV stream than SD too big, but along with the development of compression technology, the mainstream H.264 compression technology, have been able to do in 1080p@25fps, stream is 2 ~ 4Mbps, equivalent to 4CIF (D1) quality 512K ~ 2M 2 ~ 4 times, consistent with quality improvement rate. Hundreds (thousands) Gigabit Ethernet port theory at the rate of 100 (1000) Mbps, the actual availability rate was 30 ~ 40 (300 ~ 400) Mbps, so each Lu Bai (thousand) Mega port can carry 10 (100) video traffic around the road.
Considering the TCP/IP network packet collision, collision and other uncertain factors, our actual configuration or set aside margin, as far as possible to reduce the port (especially the uplink port) traffic load. The general configuration of the 48 Port 10/100M adaptive band 2 port Gigabit uplink module switches as the access layer switches, each workshop center configuration 2 units, each switch are respectively connected with 40 IP cameras around Taiwan. Each exchange connection HD and standard definition IP camera number should be the same, to keep the upload traffic equilibrium.
Center is equipped with 2 sets of video server, 2 stores, 4 TV wall video workstation (take 16 HD display), 2 management workstation, a total of 12 Gigabit ports. Need to match a 24 port Gigabit port, the convergence layer switch 2 Gigabit module slot.
Such a network architecture has been gradually clear: fast access, Gigabit convergence, million to the core. In fact, the link monitoring center only Gigabit can, what reason? The following sections will describe the control center.
A center network topology diagram as follows:

The solid line shows the original link, the dotted line represents the Gigabit link
Integrated wiring UTP physical link network with over 5 classes, of course can use 6 kinds of better. Access center and gathering in the same cabinet, thus converging Gigabit port can be directly used and the access connection, no need to increase the optical module. If the access switch in the field, then access and aggregation can adopt Gigabit multimode optical fiber cable connection. Aggregation and core connected by Gigabit fiber is the best. Because the plant is large, some of the front camera distance access switch over 100 meters, the UTP link in this section to 4 core multimode fiber, the fiber ends with a 100M optical fiber transceiver, photoelectric conversion.
Summary: transmission network composed of generic cabling and network switches, small scale projects as long as two layers (access and core), the system for large-scale larger, design for the three layer architecture (access, aggregation and core), system speed and meet the fast access, Gigabit convergence, thousand (million) Mega core. This is a very mature network architecture, any network configuration and implementation experience of the engineers are capable to design.
4.3Center Design
Video servers, storage devices, TV wall, video workstation are arranged in the center.
4.3.1The video server
The video server, video server and factory here mentioned media mentioned (DVS) is not the same, the main function of DVS is a digital to analog video coding, video server here said is encapsulated and forwarded to the storage equipment up to the front camera transmits video streaming, video playback at the same time to response the workstation (real time and video) request, take out the corresponding number of the video stream from a storage device, and a streaming media server.
By the current limit of PC architecture of the CPU resource management, general video stream does not exceed 64, in order to improve the stability of the system, we suggest that each connection is not more than 50 road. In this project we set management is 40, thus greatly improve the stability of the server, but also to ensure the other terminal in response to the request with the server.
The server specific selection should adopt Xeon processor (2), more than 2G of memory. Each server configuration monitoring video management platform software.
The sketch map of server, video streaming platform and management work flow:

4.3.2Storage devices
The current IP control engineering of mainstream storage uses the IP SAN form, each storage by 2 ~ 4 Gigabit Ethernet ports linked to the IP network for receiving video server, video stream forwarding. For storage, we are most concerned about is the size, because this will be the total cost related to the system. Here the HD and SD video storage capacity of calculation.
Single Channel HD 30 days storage capacity = 3Mbps (average rate) x 60 x 60 x 24 x 30 / 8 (small B B), 1024 (M G), 1024 (G T) = 0.93T, 1T capacity for convenience of calculation.
Single sign – 30 days of storage time capacity = 1Mbps (average D1 stream quality under) x 60 x 60 x 24 x 30 / 8 (small B B), 1024 (M G), 1024 (G T) = 0.31T, 0.3T capacity for convenience of calculation.
So each workshop according to the 50 high-definition 30 logo clear, storage 1 months time to count:
The total capacity of = 50 × 1T+30 × 0.3T = 59T
The 59T for the theoretical capacity of 24 hours full real-time video, practical application into account when closed down the factory, production line maintenance, stop working at night, as well as the use of video motion detection methods, the actual capacity can be reduced, the 48T has enough.
The total flow of each workshop 80 video = 50 × 3Mbps+30 × 0.3Mbps=159Mbps
For storage, using 2 port Gigabit network interface, duplex speed can reach 4G external, internal storage disk read and write the total throughput of the maximum value is 400M, a workshop center are to store the write code for 159Mbps, this value is can handle over for storage, but also the residual bandwidth for video playback (read the stream).
Because the storage cost is higher, the rational allocation of storage, get a higher price, the owners are concerned, must also hold each designer. In general, the storage device has a maximum capacity (with expansion chassis groove position), we use the maximum capacity in the foot, diluted storage host cost can maximize to each T hard disk capacity. For example, a 24 slot to store, with only 1 1T hard disk, so the storage unit of T capacity cost is high; if the 24 slots are full, then the cost of each T will be very low.
We analyze the total flow and the total storage capacity of both permission in the above, the available single IP SAN memory, the 24 slot 24 slot expansion of host chassis, a total of 48 slot. If the current mainstream cost-effective 1TB capacity SATA disk, can get 48T of storage capacity, if the SATA disk 1.5T, can get the capacity of the 72T.
4.3.3Display and control center.
At present, the HD video, decoder no ready-made hardware decompression can be used to directly output to the TV wall. So the major approach is to install the client software on workstation, video decoding, output to the screen using the high performance video card PC machine. Installation of 2 pieces of double DVI each PC machine (or HDMI) high performance graphics output, can be each 4 independent output. Our center TV wall into 16 HD display, need to configure 4 video workstation.
There is a need to explain, video image PC graphics each output can be a single, also can be the image multi screen separated, supports 4, 9, 16 up to 64. Center of TV wall display of which 5 units used to display 16 separate images, so that the 80 way video all on the wall display, the remaining 11 sets of single screen fixed or polling shows.
TV wall using 16:9 Hd 1080p special 42 “PDP display, in order to improve the display effect and stability. The HD display support composite video, DVI, HDMI, YPrPb component interface, can display all kinds of signal source.
Because of habit, common security personnel on duty like rocker, keyboard utility dedicated, switching and control to the video image, the IP monitoring framework, directly to the keyboard and mouse only computer practical, the operation is very inconvenient. Therefore, in order to solve this problem, we in the management platform software, configuration of a USB interface with the rocker keyboard, with easy to use operator.
On the operating table configuration a management station, can carry out menu settings for all IP camera installed in the workshop, for the configuration and management server, storage device. Management workstation also set different permissions, so that different operators.
4.3.4Combining with the production management
The IP monitoring system is not only as a security monitoring system, but also become a production management aids. Through the open interface for the monitoring and management platform, to the production management system (MES) is two times the development of docking, the pipeline exception occurs, can be video images timely call site, if the production line of unmanned, via SMS or 3G video can be sent to the management of the mobile phone, greatly improve the the production management system of intelligent chengdu.
The two development work in this project is implemented by the construction unit of production management system, our party is responsible for opening interface and coordination.
4.4Design of the total control center
The factory set up a control center, 5 workshops on the following sub center can monitor and manage the overall, view real-time image and video data call. The control center is provided with 24 large screen television wall, as the control center of plant management.
From the front of the center architecture can be seen, the camera video stream of each shop most already in the local memory and the realization of the management, the normal operation even if the total control center does not run it will not affect the center. If the total control center does not call center, see video, network between control and center flow for the 0 basic; if the total control to video data of the following calls, according to the single screen display to calculate the single road, 32 road up to HD streams, for example the most up to 32 x 3 = 96Mbps. In view of this, we believe that the core switch convergence layer switch control center to control the Gigabit link can, of course, from a long-term point of view, wiring system is a one-time investment, the trunk should adopt Gigabit fiber optic cable, but the application of monitoring system of Gigabit rate was enough, it can also reduce the network switching equipment cost, all Gigabit equipment prices than many of Qian Zhaogao.
32 channel video output, configuration 8 units and 4 output video workstation. In addition to set the 6 command dispatcher workstation, can be arbitrary video monitor, see.

The general topology IP video monitoring system diagram
The control center is equipped with a video server backup and backup storage, can be used to take over immediately in the center of video server crash failure time, will all the video bitstream switching the center to the control center, it converges to the core of the Gigabit backbone network really play the role of a single plant, front Center General stream calculated as 195Mbps, can fully meet the non blocking in Gigabit network. At the same time the system alarm, to remind staff to processing center server problems.
The core switch with frame type Gigabit core switches, configuration 1 engine, 1 pieces of 24 port Gigabit port plate and a 24 port Gigabit optical module board backplane capacity is greater than the sum of all ports, full duplex full speed.
Big screen with 24 pieces of 50 “DLP splicing wall, 3 × 8 arrangement, the seam less than 1mm. Due to the current DLP the highest cost-effective products for 4:3 products, a single maximum resolution of 1280 x 1024, for a single screen is not fully display the 1920 * 1080 resolution is 2000000 pixels, so the output can be used when the lower screen resolution, in order to meet the resolution of display equipment. If the point to point to display full screen, it can screen splicing system for multi screen display and roaming, 3 × 8 DLP display wall on the whole can reach 10240 * 3072 resolution.
If the DLP screen splicing 16:9 formed the mainstream, and the price is reasonable, then all use 16:9 1080p widescreen, display system can achieve perfect pixel matching with the front camera.
4.5Management platform of choice
Currently on the market can provide management platform software video surveillance manufacturers a lot, there are third party also have some hardware manufacturers. Generally speaking, the third party platform software is taking the open road, IP camera fully supporting the brand, with various specifications, for the owners and builders, in such third party platform as the basis to build the IP monitoring system is very convenient, can be free to choose the characteristics of the IP camera brand products, integrated into the system, without fear of each brand products is not compatible, not management. Support for IP camera products more platform software, priority should be given to.
We also tried using solutions with some manufacturers a full set of hardware, software products, this is some security manufacturers design their own development, for their own products, integration is very good, there are also many highlights exist (such as ISCSI application), but can only access its own brand products, incompatible or compatible rarely the other products. IP camera and there are so many unique on the market can choose, such as Panasonic wide dynamic, low SONY illumination, the stability of PELCO, how can we as a platform, these excellent products will be shut sb.?
Open — is the mainstream ideology of the era of the IP, design of IP monitoring system should conform to this idea.

5、Analysis of three kinds of monitoring architecture economy
There may be some peers and owners also very understanding of the IP monitoring system is not, that IP system cost is very high, is not the average person can receive it, but through this case, and the three main structure analysis, can completely subvert the concept of cost expensive.
Please look at the next table analysis


Simulation system

IP SD systems

IP HD systems

Fixed camera


1~5000(domestic and imported brands gap)

5000 ~1.5 million(imported brand)

Transmission line

SYV video line 2 yuan / M

Domestic super 5 lines 1.6 yuan / M

Domestic super 5 lines 1.6 yuan / M

Power cord

RVV*1.02 yuan / M

RVV2*1.02 yuan / M; POE power supplyPower line obviates separate

RVV2*1.02 yuan / M; POE power save
Power line alone

Transmission equipment

A few hundred meters without additional
Transmission equipment

Network switches, domestic can
Do 100~200 yuan / port

Network switches, domestic can
Do 100~200 yuan / port

Video equipment
(30 days of storage for example)

DVR, 16 D1 image quality,The capacity of 4T, 800~1000 yuan per Road

Video server and storage, 64 road is a set of,20T storage capacity, equivalent to 1000~1200/ Road

Video server and storage, 50 road is a set of,50T storage capacity, equivalent to 3000~5000/ Road


According to the domestic 400~700/ Road



Management platform software

Can not

Domestic brand 50~200 yuan / road

Imported brand 1000~2000 yuan / road

Camera + transmission +
Total storage + platform
(not including cable)

2200~3700 yuan / road

2150~6500/ Road

9100~22000/ Road (but HD video cameraAngle range is 5 times the standard definition, a
Can replace 5 logo or a logo clear fastball)

From the contrast can be seen, IP SD systems than simulation system to increase the number of cost, equipment, reasonable selection of elaborate collocation also can accomplish even lower cost. HD systems subject to the camera itself price and storage cost, software, each cost is not economic, but from can replace 5 or 1 logo signs Qing Qing ball machine point of view, the cost is not high.
In the above example, if the workshop without using high-definition cameras, covering the same site selection standard number Qing camera will increase 3 ~ 4 times, the cost will increase a lot.
But in the system to meet the actual flow, storage capacity, select the configuration and products with the best cost-effective, is an important means to lower the cost of IP monitoring system.

6、Effects of several disorders in IP HD monitor promotion
From the existing mature products currently on the market point of view, promote IP HD monitoring system also has several defects or disorders.
To achieve low illuminance:
IP HD cameras generally use COMS as the photosensitive chip, the biggest disadvantage of COMS is poor imaging quality under low illumination, cannot implement CCD as a low sensitivity. Therefore all COMS megapixels high-definition camera of the fatal weakness is the low illumination effect is poor, even in the case of adding infrared light, the effect is still not as good as CCD. To improve the defects remain to the principle of COMS, and the processing chip technology development.
The high price of storage:
Another factor impeding the application of IP HD monitoring system is the storage, the storage technology mainly is restricted and hard disk storage capacity. If the hard disk storage density is increased several times, but the price continues to decline, the storage cost of each HD video can be reduced to the current DVR storage spaces, the HD system instead of standard system is the point the day and await for it.
The national industry standard is not perfect:
HD monitoring system construction acceptance standards and specifications without national design, related.
The user’s use of inertia:
Used to the simulation of SD, the cognition of the IP system is not enough, and vigorously promote the needs of manufacturers and integrators.

7、IP HD monitoring project at present best practices
In view of the full IP HD monitoring project investment is large, not every owner can bear, we found out the best practices for the SD and HD mix mode, which is the hybrid architecture.

(1)The IP monitoring system
(2)The key occasions, selection of IP HD video camera
(3)The open support high-definition camera intelligent video management platform software
(4)Configure the network, storage system reasonably, in order to achieve the best price

How to choose a suitable lens installed surveillance Camera

Below is a table of 1/3 inch lens

Camera lens






























Lens mm number and the corresponding distance parameter table

Lens parameters








Camera angle








The best distance








Monitoring the angle of a shot, a proportion of the distance
The relative aperture
F- F F=f/D f= the number of aperture, focal length, aperture D= lens
The focal length of the lens 2.8mm 3.5mm 4mm 4.8mm 6mm 8mm
1/3 “CCD from the angle of 86.3 ° 67.4 ° to 62 ° and 52.2 ° 42.3 ° 32.6 °
The distance of the object 4.3m 5.4m 6m 7.3m 9m 12m
The focal length of the lens 12mm 16mm 25mm 60mm 73.8mm
1/3 “CCD from the angle of 22.1 ° 17.1 ° 10.6 ° 3.5 ° 2.9 °
The distance of the object 18mm 25mm 38mm 120mm 150mm
In order to monitor display 5m objects shall prevail
Lens mounting part diameter of 25.4mm
Lens mounting datum to the focal distance of 17.526mm
C type lens mounted to the camera CS interface to add 5mm connecting ring thickness
The main difference is the size of the lens:
Lens more look closer, but the visual range is wide; the lens more see farther, but the visual range is narrow.
Our baby classification inside, dome camera can choose 3.6MM or 6MM lens;
30 meters waterproof infrared camera can choose 3.6MM, 6MM or 8MM lens;
More than 30 meters waterproof infrared camera can choose 4MM, 6MM, 8MM, 12MM, 16MM, 25MM lens (lens. These are big CS lens all metal)

Calculation method for monitoring the camera angle
The 1/3 camera as an example:

The lens size








The corresponding angle








The corresponding corner








The best visual range (m) corresponding to the size of *2- = shot dead
Note: the best visual range is dead outside the distance
Such as: 12MM lens visual angle of 22 degrees, the visual distance the best is 24 meters (including dead distance), according to the formula: visual range of the best angle of 22 degrees, the visual range camera 4 meters to 24 meters


F=2.8mm lens, shooting distance is 1~4 meters

 Shooting angle 95 °


F=3.6mm lens, shooting distance is 2~6 meters

Shooting angle93°


   F=6mm lens, shooting distance is 3~15 meters

Shooting angle53°


 F=8mm lens, shooting distance is 4~20 meters

Shooting angle40°


 F=12mm lens, shooting distance is 5~25 meters

Shooting angle25°


 F=16mm lens, shooting distance is 5~30 meters

Shooting angle20°


F=25mm lens, shooting distance is 20~80 meters

Shooting angle15°

The choice of lens: lens mm smaller numbers, more open field of vision, but look closer; lens mm higher numbers, vision and more narrow, but see the farther the distance, the two can not have it both ways)
The calculation formula of camera lens
Calculation formula:
Department of field of view and the focal length of the calculated field refers to the uptake of object size, field size is the distance to the lens to be ingested objects, camera head and image size required to determine the.
The focal length of the lens, field lens to be calculated as follows: the size and distance of uptake of objects:
F: the focal length of the lens   W: image width(object imaging width in the CCD target surface)
W: object width
L: object to camera distance
H: image height (an image of an object in the CCD target surface height) field (uptake of scenes) height
H: object height

The CCD target surface

Specifications and dimensions















Because the camera screen width and height with the TV screen width and height, the ratio is 4:3, when the L invariant, H or W increases, f becomes smaller, when H or W unchanged, L increases, f increases.
Calculation of angle of view
If the horizontal or vertical angle can be calculated according to the formula of the width and height. Horizontal view angle β (horizontal viewing angle) β =2tg-1= vertical field of view angle Q (vertical viewing angle) q=2tg-1= type W, H, f. Horizontal view angle and the vertical angle of view as follows: q= or =q listed in Table 2 value B the horizontal view of different sizes and different focal length camera layer of f angle, if the horizontal or vertical angle can be calculated from the field angle can be calculated out of the field H and field width W. height H=2Ltg, W=2Ltg for example; camera tube is 17mm (2/3in), the focal length of the lens f to 12mm, from table 2 check horizontal viewing angle of 40 degrees. Lens and ingested objects at a distance of 2m, find the field width W. W=2Ltg=2 * 2tg=1.46m H=W= * 1.46=1.059m f more and long focal length, field of view angle is small, the goal of surveillance is small.
The graphic method
As previously shown, the camera field of view by the wide (W). High (H) and the distances from the camera (L) decision, once the decision to the camera to monitor the scene, the correct choice of the focal length of the lens on the origin of 3 factors;
* to monitor the dimension of the object
* the camera and the object distance
* camera imager ruler: 1/3 “, 1/2” 2/3 “, or 1”
Graphic lens selection steps: there is a simple relationship between field of view and the focal length of the lens required. Using this relation can choose appropriate lens. Maximum width estimated or measured field; estimation or measurement camera and photographed the scene and the distance between the lens; use 1/3 “used in Figure 2, the use of 1/2 lens used in Figure 3, the use of 2/3” lens use figure 4, using a 1 lens use figure 5. Method: on the icon to W and L axes 2-5, find out the focal length of the lens should be used. To ensure that the object is completely contained in the field, should choose the coordinate intersection, numerical surface that line indicator. For example: wide field of view 50m, distance of 40m, using the 1/3 “format of the lens, at the intersection graphs of 4mm lens than partial line a bit. This shows that if you use the 4mm lens can not cover the 50m field of view. And with a 2.8mm lens can completely cover the field.
Wherein, f represents the focal length, V represents the vertical CCD target surface height, V represents the observed object height, H represents the level of CCD target surface width, H represents the observed object width.
Give an example:If 1/2 “CCD camera observation, the object to be measured 440 mm wide, 330 mm high, lens focal distance of 2500 mm objects.
Can be calculated by formula:Focal length f=6.4X2500/440 = 36 mm or 36 mm focal length is f=4.8X2500/330
When the focal length is numerical calculated, if there is no corresponding to the focal length of the lens is very normal, then according to the catalogue choice of similar models, the general selection value smaller than the calculation, this view will be greater.
In order to obtain the same point of view from the 1/3 “and 1/2” 1/3 “CCD CCD camera, camera lens focal length must be reduced; if the same focal length in 1/3” CCD and 1/2 “CCD camera lens, the situation and how? 1/3” CCD camera than 1/2 “CCD camera is decreased obviously, at the same time image 1/3 ″ CCD camera, image on the monitor than 1/2 ″ CCD amplification, produced using the telephoto lens effect. In addition we select the lens should pay attention to such a principle: small size target surface CCD can use large size target surface CCD cameras, not vice versa. The reason is: if 1/2 “CCD by 1/3” camera lens, the light becomes smaller, the color will become worse, even image will defect; on the contrary, the amount of light will become large, the color will change, image effects will certainly be better. Of course, integrated a variety of factors, the camera or to choose the best matching lens.

HD-SDI Camera

Why HD-SDI Camera
With the digital, HD security monitoring system to speed up the rhythm, high-definition network products but also have good performance, but even so, still can not ignore its unsatisfactory places, such as delay, loss, high bandwidth, codec. In this regard, manufacturers and users in addition to helplessness, still continue to seek better HD solution. Under this demand, created a new application — will broadcast standard SDI is introduced into the field of security applications, real-time HD on real significance, HD camera based on HD-SDI standard interface is one of the representative.

How to treat the SDI Camera? Why will appear this kind of Camera?
Application of the HD-SDI concept from the broadcast, the perennial in agreement / broadcast technology used in recent years is introduced as a platform for high-definition video surveillance, in fact, is derived from the network monitoring spent more than five years still can not successfully replace CCTV scheme, so that transmission of uncompressed / low delay / HD-SDI scheme can easily the installation of a new force suddenly rises.

A lot of people on the SDI camera is still a relatively vague concept, how to clarify the concept of SDI Camera?
HD- SDI is based on digital bone, CCTV concept of operation – >, which is based on the digital signal according to the HD-SDI specification in the video above line /BNC interface transmission of uncompressed video / audio and control / power in a video online, and the installation is exactly the same way as the CCTV, the agent / distributor / engineering business some do not need to learn extra costs and inputs such as network monitoring, after sale services / human.
HD CCTV on the market is also known as the CCTV HD (for its shape) or digital HD (the bone), but the latter is easy with the network HD confusion, because some users in the past between analog / network, has used the analog / digital to distinguish, so based on this point as well as for the applications of consideration, in the face of customers when introduced, will use CCTV HD (HD CCTV) and analog / network make a difference.

What is the core technology of HD-SDI Camera?
The core technology of HD-SDI in SDI chip, Video Codec, Sensor/ISP and other producers, to have the network HD manufacturing strength of the manufacturers to enter the threshold is not high, so the industry is taking a wait-and-see, not a barrier to entry, an estimated 2011 the second half of the show is contending event occurred.
The current mainstream HD-SDI resolution on the market for 720p (1280×720) /1080p (1920×1080), BNC interface interface mostly go video line output, but also has direct optical interface, the application of optical fiber in HD era is expected to substantially growth, its wide frequency band, low loss, interference resistance, light weight and scalability also, this trend is worth attention.

The SDI camera has the network camera there is nothing comparable to this advantage, these advantages are? Whether and what problem in development, how to solve?
Without distortion, high reliability: HDcctv digital signal is not transmitted via the compression format on coaxial cables, unlike the IP image lag, tailing or dropped frames, reliability is high
 · Real time image HD Grade: HDcctv delay in the transmission, much better than HD IP, is better for real-time monitoring;
 · The total cost of HD upgrade low: coaxial cable using existing (RG58/59) upgrading from D1 to HD, as in solution by 380 TV lines upgrade to high solution 520 TV lines as easy;
 · The operation interface (UI) similarity: for contractors or user, its establishment and operation and the CCTV is, no extra costs of learning;
· Multi task transfer, festival wiring: can transmit video, two-way audio, two-way control, power supply at the same time, coaxial cables, wiring saving cost;
· To provide intelligent monitoring (VA) required HD image: HDcctv provide high-definition image is not compressed, and can be best HD image sources of supply of intelligent monitoring required.
So on those requirements of high definition and real-time monitoring of the occasion, such as a casino, live etc.. The SD to HD’s point of view, originally using CCTV cell can add the HDcctv front-end and back-end product can be directly upgraded to HD monitor, do not need to change all the high-definition network system and high cost; to customer service service or training point of view, the majority of users and engineering are no IP background, so that plug and play HDcctv very attractive for this type of users, they can be some indirect cost down conversion increased for network monitoring

Why will release a SDI Camera? What are the main problem?
Provide SDI camera to the customer as a project and to the CCTV customers do HD upgrade. The existing CCTV users in some field to use HD replacement and don’t want to completely replace the monitoring scheme for the network, you can use the CCTV HD as a substitute.
The market is currently in early adoption stage, the mostly technical customer, whether the public / private sector, important is to provide systems integration solutions complete was able to persuade the customer, how to use CCTV/IP integration is a key.
As with other types of surveillance cameras, HD-SDI cameras have very high request in resolution. Because only the HD signal source to make HDcctv play their HD color, this of course requires the camera to million pixels reached. Because of the high resolution is often accompanied by a large amount of image data, which often affects the frame rate, therefore, only mega pixel camera also can not guarantee the high quality of image. In contrast, satisfy the network camera any given HDcctv standards must be able to provide some resolution, frame rate and color fidelity, which always make sure that the video quality. Full HD 1080P is the best choice. The current mainstream HD-SDI resolution on the market for 720P (1280 × 720) /1080P (1920 * 1080).
2、Gamma correction
When the camera work in certain circumstances, often can make the display images of people look too bright or too dark, so under the possible conditions to do gamma (gamma correction). It can enhance the dark part of the image, but does not change the brightness brighter part, so as to make the image look more levels.

The HD-SDI transmission interface
HD-SDI camera is another key is camera interface selection. HD interface on the true meaning of the including HD-SDI, YPbPr, HDMI, DVI these, and from table 1 it is seen clearly, the comprehensive advantages of HD-SDI interface in the HD digital interface. The HD-SDI interface is a relatively good high-definition interface, and HD-SDI interface is currently broadcasting industry standard high-definition interface.





Port number 


Transmission format   





Signal transmission mode  

No signal compression conversion

Analog signal 

No signal compression conversion

No signal compression conversion

At the same time, audio transmission


Does not support 


Does not support

Broadband transmission 





The furthest distance  






HD-SDI camera and HD IP Camera performance comparison

HD-SDI Camera

Ordinary HD IP Camera

The imaging chip



Shutter type

Global shutter

Rolling shutter

Pixel size


2.2um or less


1080P, 720P optional

1080P (5M Pixel CMOS chip ROI)

A/D converter






Data interface


Fast Ethernet

Broadband transmission



Data output format



Video output connector

BNC type connector


Image processing functions

Gamma, hue, saturation, sharpness

Gamma, hue, saturation, sharpness

The shutter

Automatic / manual / single, software programmable


White balance

Automatic / manual / single, software programmable



Automatic / manual / single, software programmable


Image lag

About 40ms


Signal to noise ratio



Automatic aperture

DC driver


Additional features






The factory level

Industrial grade


Compared with the HD-SDI camera with IP Camera, mainly has the following four advantages
 ·Uncompressed: HD-SDI digital signal is uncompressed format in the video transmission line, unlike the network easily fall / break, reliability is high;
· Low latency: the HD-SDI has a lower transmission delay than high-definition network, real-time monitoring of the better scheme;
· Easy installation: to project developers or users, its setup is operating with the traditional CCTV, no additional cost of learning;

 · Low cost: the total cost by simulation to upgrade to HD is low, upgraded from HD to D1 to use the existing video line, only need to replace the front end equipment, without re wiring.

What is the difference between DVR, NVR and IPVS?

DVR (digital video recorder)
Is the second generation of monitoring system in recent years after the rapid development of analog recording system. Uses the microcomputer and the Windows platform, the installation of video compression card and the corresponding DVR software in the computer, different types of video card can be connected to the 1/2/4 video, real-time video and audio support, is the realization of digital upgrade options for the first generation analog monitor system.
The characteristics of DVR system: video, audio signal acquisition, storage, mainly in digital form, high quality; system function more powerful, perfect; exchange of data and information system can be applied with good flexibility. However, because of its limitation technology architecture, digital hard disk recorders has been unable to solve the network remote monitoring in the environment of long delay, not multiple simultaneous monitoring, high integration degree centralized monitoring etc..
The reason is that, DVR system from the control point to the monitoring center for the analog transmission, with the first generation system has many defects, need laying long-distance video transmission (rent) cable, installed video transceiver equipment in the cable system at both ends, the high cost of construction, maintenance is not easy and the cost of maintenance is large. Transformation of the system is only suitable for traditional monitoring system, monitoring system and is not suitable for the new requirements of remote video transmission (more than 1 ~ 2 km) system.

NVR (network video recorder)
With the development of Internet, broadband network technology and information technology, in recent years, a new force suddenly rises. The remote video monitoring system based on embedded DVR server Web, commonly known as the 2.5 generation of monitoring system of embedded DVR network video recorder NVR.
In the video surveillance system, NVR is the analog recorders and hard disk video recorder ideal upgrade product, is a stand-alone operation equipment from the windows operating system and computer with the implementation of DVR in the original basis. Because NVR takes a highly integrated chip technology, has the function of digital video, advanced storage and playback, does not need to be replaced or stored video, without computer cooperation and daily maintenance, therefore, to achieve a high resolution (up to Full-D1 resolution), real-time monitoring of high quality, and easy to use.
In simple terms, the NVR system will be the traditional video, digital audio and control signals, through the network interface on the NVR device, to the form of IP packets transmitted on the network, on the basis of DVR, the realization of the system’s network.
Application, although NVR system has a fast computer processing power, digital information anti-interference ability, convenient and quick query records, clear video image and single display multiple images etc.. But, in essence, NVR not only solve the defects of analog transmission in DVR system, there is no good solution to more management network video transmission flow brought by the. In fact, each NVR to form an independent monitoring center, resulting in greater complexity to achieve full network monitoring. In the remote control, multi-level scalability and network ability, still need to improve.

IPVS (network video monitoring system)
Video monitoring system fully networked (IPVS IP Video Surveillance), the video from the image acquisition device output is digital signal, using the standard Internet network as the transmission medium, the international standard TCP/IP protocol, using streaming media technology, video multiplexing transmission network, and through in online video streaming server, complete the video stream forwarding, alarm operation, to realize the whole monitoring system command, scheduling, inventory, authorization control functions. In addition, alarm, access control, patrol the front-end equipment output digital signal, but also by the combination of multi network mode, through the network transmission and multiplexing, management and control in the same platform.
The complete network video monitoring system based on IPVS, the whole system and the standard TCP/IP network protocol code device, a video monitoring system network camera, users can use the standard network equipment, network server, network storage devices and computer products. IPVS not only has the local traditional digital monitoring system with computer processing ability, digital information anti-interference ability, convenient and quick query records, clear video image and single display multiple images and other advantages, but, to effectively play the advantage of broadband network, through the IP network, the monitoring target any combination of local coverage can be reached. A complete, integrated system, really adapt to the current video monitoring system for remote, real-time, centralized control requirements. Users only need to sit in the control room with a click of the mouse, you can quickly complete the digital search and recovery of function, and, the digital image is more clear, more easily by the recording and playback.
All the advantages of the full IP video surveillance system not only has the DVR, NVR, and other more advantages: fully networked IPVS solutions, can be compatible with and support a variety of original analog video equipment, protect users investment, protection of business environment. IPVS system can extend out more monitoring and analysis function, let video monitoring and other applications in the IT environment with an enterprise become possible. In addition, IPVS solutions, in the application of multimedia digital, networked, intelligent, systematic and large scale network ability, advantage is quite prominent.

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