On the return of the era of high-definition monitor
The past two years, was a period of rapid development of the security industry, the rapid development and modernization of the city's economy, as well as to build a harmonious society, the work of the security monitoring system of urban industry made many new requirements and issues. At the same time, safe city construction contractor Olympics, for the development of the security industry to provide a broad platform for the development of technology in the industry. The security industry currently occupies a very important position in video surveillance products, while the rapid development of the security market, but also exposed many problems. (Switching Power Supply)
With the rapid development of video surveillance technology, users are demanding video surveillance products is also rising, clarity requirements are higher, more complete functional requirements, performance requirements, more stable. How to see the facial features airports, banks, shopping malls and other places people? How can see the high-speed vehicle license? How can quickly and accurately find the crowds and noise of the train station, goal occasion stadiums, squares, etc.? ....... These are the video surveillance product problems to be solved. (Polyester
Throughout the current video surveillance product market can be said to be a pack and play era, there has been a lot of research and development strength, the market share of these companies, but companies with high product development to a certain stage, and now have entered a bottleneck period. A very important performance video surveillance products on the market homogeneity serious lack of people, "eye-catching" products. Motion detection, linkage alarm, dual-stream, multi-channel D1 and other products, which two years ago in a very advanced technology, but now almost all the products can be achieved. A product homogeneity problem is brought on many projects, competition has evolved into a simple price competition, serious pressure on the manufacturers, engineering margins. (Beach towels)
Video surveillance products experienced figures, after two important stages of development of the network, the development direction of video surveillance products, where?
First, the definition needs to highlight
"Let us see more clearly," this is a very urgent needs of many users in the use of video surveillance products raised. ? President of the United States the authority of IT market research firm MultiMediaIntelligence Mark Kirstein mentioned video surveillance equipment market to promote the development of four technical factors: megapixels camera, high performance codecs, powerful analytical techniques, as well as easy from closed circuit television ( CCTV) migrate to all the underlying technology IP / networked video surveillance. From his words, we can see that the four technical factors in megapixels camera, high performance codecs and IP network technologies, both product-related and high-definition, high-definition products on behalf of the collection, coding and decoding, network transmission direction of development. (Pump accessories)
Second, what is HD?
"HD video surveillance" has become a hot topic in the security industry, a growing number of security vendors have also launched their own "HD" monitoring product. Throughout the "HD" product on the market monitoring, we find that different vendors have different understandings of standard-definition "HD" effect will vary. Then, "high-definition" concept video surveillance industry what? What is the real "HD"? (Iodide)
We look at the definition of high-definition digital television technology is. (Generator oil)
In the broadcast television industry, digital television and HD video formats currently there are three: 720P, 1080i, 1080P, which screen aspect ratio is defined as 16: 9. () 720P that is 1280 × 720 resolution, 1080i and 1080P is 1920 × 1080 resolution, the suffix "i" and "p" respectively interlaced with progressive scan. Wherein, 1080P is the highest level of high definition video resolution standards. For fast-moving target image acquisition, compared to interlaced, progressive scan can get a better motion picture, it will produce an interlaced image shaking phenomenon. (Generator oil)
Security industry has no uniform standard definition, reference the broadcast industry standard definition of high-definition digital TV, the industry generally recognized definition at least to meet or exceed the 720P (1280 × 720 resolution). (Chair)
Third, the network is the basis of high-definition applications
To achieve true high-definition monitor, to be collected from the video source, the encoded video signal compression and transmission of video signals, playback video browsing, video files link full support for HD. For customers, high-definition only includes the front only, platform, storage, browsing, display and other aspects of sense. (Driving IC)
After the acquisition of uncompressed HD video signals have both analog and digital transmission, analog transmission generally use the YPbPr component transmission, all the way to high-definition video signals require simultaneous transmission of three coaxial cables. Digital transmission generally use DVI, HDMI or HD-SDI transmission, wherein the transmission distance of only a few meters DVI or HDMI, is not suitable for monitoring the transmission, and HD-SDI can be transmitted, although about one hundred meters, but demanding coaxial the price of the cable is also very expensive. However, if the front-end to high-definition video compression for efficient processing and IP transport network by then its transport costs and SD monitoring network transmission costs considerably. (Showcase)
Currently DVR video signal processing, video capture and video encoding is divided into two portions. In the video signal acquisition, most of the DVR are analog video inputs are used CVBS BNC interface (ie, the composite video signal) input. The maximum resolution of the composite video signal is D1, DVR inside the composite video signal is collected in accordance with D1 resolution, quantization. DVR currently no YPbPr analog component interface, or DVI, HDMI, HD-SDI and other digital video interface. In the coding section, DVR video capture for each channel signal can be encoded into CIF, 2CIF, DCIF, D1 resolution, etc., but can only encode a maximum resolution of D1, 720p or do not have the provision 1080i, 1080p encoding capability. Therefore, the current definition monitor DVR can not be achieved. (Protective suit)
Visible, to achieve high-definition monitor, obtain from the monitoring system to consider high-definition, and the network is the basis of high-definition monitor system applications. (Chargers)
Fourth, HD network camera is a prerequisite for high-definition monitor
Analog products and digital high-definition products in comparison there are many design flaws, making it difficult to have a big increase in resolution, frame rate, etc. In the current technology infrastructure. Take clarity, the existing analog CCTV surveillance system, cameras capture vertical resolution, PAL standard 625 scan lines, the existing ultra-high-definition products reached 540,600 lines of basic analog system has reached the limit. The network camera also no upper limit (megapixels network cameras can easily see the 1000 line above). So high-definition camcorder on the market for network cameras are monitored. (Drill)
HD network camera means can press more than 12FPS continuous acquisition is greater than the maximum resolution 720P (1280 * 720), and even meet or exceed 1080P (1920 * 1080 resolution) webcam. It meets the above definition 720P HD standard, could be interpreted as megapixels level, we also called for the megapixels HD network camera network cameras, network cameras megapixels than traditional analog cameras, network cameras has the following advantages ordinary tablecloth :( )
Adopt megapixels sensor that can get more video information, generally up to 1280 × 1024,1392 × 1024,1628 × 1236 or 2048 × 1536 resolution;
Using megapixels camera, lens and megapixels ordinary test shots in the same environment, megapixels lens can better meet megapixels sensor, access to the clearer the image. (Showcase)
Image display higher quality, better able to capture the details;
Progressive scan CCD / COMS dynamic picture performance more fluid;
Supports HDTV widescreen output mode (16: 9);
Coverage, the same surveillance area can replace existing cameras and a plurality of fixed-point omnidirectional camera. (Boric acid)
The camera's resolution depends on the sensor performance, CCD sensor compared with two CMOS, CCD sensor sensitivity, resolution, noise control, high-quality image output, dynamic image performance outperforms other COMS, so analog cameras and SD Webcams mostly chosen as a photosensitive element CCD. But CCD response speed is low, it does not apply to high-resolution progressive scan HD surveillance cameras used, and therefore widely used in high-definition network camera CMOS sensor. (Oil)
Image compression format directly determines the transmission network, video storage, back-end processing requirements, but also to a large extent affect the image quality. Currently in high-definition network camera is widely used image compression technology JPEG / MPEG-4 / H.264 three ways, each has a different compression characteristics. As single JPEG can achieve the highest picture quality, and the camera itself processing platform requirements are low, but continuous maximum bandwidth image compression; H.264 can obtain the highest compression ratio, but the camera itself processing platform requirements highest. In order to meet a variety of application requirements and network environment, relatively high-end high-definition network cameras also have three coding capability and dual-stream, multi-stream function. (Dispersant)
Fifth, the question facing the high-definition monitor
HD network cameras make a qualitative leap in image clarity, but also to the high-definition monitor system has brought a series of practical questions:
Network bandwidth tension: the greater the resolution, ultra high-definition, means that during the time stream data transmission will increase, increase network bandwidth pressure.
Huge storage space: data traffic doubled, increasing the recording capacity, the network storage pressure.
For central control, management software and hardware performance requirements grow exponentially;
For recording video management and post-hoc analysis of workload will be doubled;
Investment costly. (Water repellent)
Therefore, in the pursuit of high quality, we must also consider our customers to solve the above problems.
Six high-definition monitor demand application
Technical challenges faced by the above definition monitor can be solved by the application. Under the current situation, the user should not blindly pursue high-definition. If all the front-end monitoring points use HD network cameras, and all real-time transmission of high-definition, then to the back-end storage and transmission will cause a lot of pressure, and cause the cost and efficiency of waste. Therefore, the design should be based on the needs of users for solutions, such as installing megapixels HD network camera in high-risk workplace design, under normal circumstances, using only ordinary resolution (CIF, D1) to transmit real-time video image, an alarm condition occurs When a high-pixel transmission of high resolution images in JPEG format, in order to enlarge afterwards, control the details. This will greatly ease the pressure on the network, storage pressure, lower investment costs. (Insulation pot)
Currently on the market there have been three-stream high-definition network camera supports JPEG / MPEG-4 / H.264 video compression in three different formats, you can set up these three stream according to the actual situation. For example: the lower stream of the H.264 video compression D1 format to a remote image transfer to the customer for real-time monitoring, while megapixels H.264 video compression format storage server for incoming real-time image recording, It also can transfer megapixels JPEG images at an alarm, easy to confirm amplified afterwards, looking for suspicious objects. (Camellia oil)
In short, we should follow the following principles: In normal transmission bandwidth real-time image smaller, but at a critical time transmission of high-definition images of good image quality. (Rain shield)
VII Conclusion
The era of high-definition monitor applications, is rushing to us! Open standards is to promote the development of high-definition catalyst. The popularity of full HD monitoring applications still have a long way to go.YARSOR will try to launch at the end of their 2-megapixel camera, into the high-definition era.
Time:2015-08-15 10:12:13