Talking about high-definition video surveillance technology and its future prospects

Since the last few years the concept of the "HD" in the video surveillance industry hot, more and more manufacturers to launch the "high definition" of products.

Through market category of "high-definition products" behind, we find that there are many products on the "high definition" of indicators to understand the performance of the effect is different. Then, the video surveillance industry, the concept of "high definition"? what is the real "HD"? this article, we talk to explore.

What is high definition?

What is HDTV? we look for high-definition digital television technology.

The main points HDTV standard definition television and high definition TV.

Standard definition TV (SDTV) refers to the image quality equivalent to the current conventional analog TV system with digital TV systems such as PAL, clarity about 500 TV lines, the rate of about 5Mbps; high-definition television (HDTV) refers to the level of sharpness and clarity about the current vertical analog TV system doubles as the aspect ratio of 16: 9 TV system, definition of about 800 TV lines or more, the rate of about 20Mbps.

ITU in ITU-R BT.1201 proposals made superhigh (HRI) for a number of criteria, its basic element is the image of minimum resolution for 1920x1080, HRI in four grades, including HRI0, HRI1, HRI2 and HRI3, resolution entitled 1920x1080, 3840x2160, 5760x3240, 7580x4320.

According to the above definition, corresponding to video surveillance, the use of analog camera module mixed monitoring up to standard definition, such as through digital processing, maximum resolution up to D1 resolution or 4CIF, about 40 million pixels, the definition in the 300 to 500 lines; the use of the IP network camera monitoring, if you want to reach 800 TV lines of resolution, then the network camera's resolution at least 1280x720 standards, about 90 million pixels, is the modulus mixed monitoring more than twice; as a megapixel network camera, met the requirements of super high definition image, the aspect ratio of 16: 9 webcam, the corresponding resolution 1920x1080, aspect ratio 4: 3 network camera, the corresponding resolution 1600x1200.

HD monitoring

High definition network camera offers video surveillance information source, it has video HD encoding and IP encapsulation, through the IP network to host high-definition images, enables high-definition monitors, video, and other monitoring functions.

On the sending end, a webcam with integrated image collection, video coding, communication, control and transmission interface, video data output via the IP network.

In image acquisition part two CCD and CMOS sensors for different needs, CMOS in high pixel has certain advantages, and CCD to monitor better the adaptability of the scene.

In video compression, different compression algorithms and algorithm implementations determines the high definition image quality and coding efficiency. Part of the communication control, network security, adaptability, stream encapsulation format and transfer features, depends on monitoring system of planning and design.

Part of the transmission interface, different network access methods, such as wireless, cable, etc., can be properly supported; in addition, some webcams also integrates surveillance required other interfaces, such as alarm, control, intercom, etc.

At the receiving end by decode, output to high definition display devices such as LCD, through the recording equipment, high-definition images for video.

Due to the high definition image stream is large, usually in the 3Mbps above, so the image record is an important part of high-definition video.

To record high-definition webcams images, we can use the following several ways:

PC-NVR

Embedded NVR

Hybrid DVR

Either way, should satisfy the following requirements, such as:

Ensure the video preservation cycle, you will need sufficient storage space;

Ensure that multiple concurrent record validation, logging process should not be a bottleneck;

Convenient, fast retrieval and playback efficiency;

With circular coverage pattern, after multiple coverage should ensure the efficiency of the recording and retrieval;

Reliability, price/performance shall conform to monitor business requirements.

PC-NVR use PC-DVR development technology, through high-definition webcams provide SDK available for secondary development, storage technologies can use DAS, NAS, IPSAN, etc.

Embedded NVR and the mixing of DVR, are derived from the embedded DVR technology.

Embedded NVR and hybrid DVR set network storage, retrieval and playback, video switching, and other monitoring functions. If the blend DVR or NVR monitor to support high-definition, then at least the following conditions:

Supports high definition network camera access;

With high definition decoding and decoding output interface (such as VGA);

Sufficient storage space or expand storage interface.

The present from time to time on several high definition network camera, CCD, CMOS sensor, support high-definition encoding 1600x1200 1280x720, can deliver up to 5 times the D1 effect shows that the rate between the 2M-8Mbps adjustable.

On the back end, the first push DS-9000 series hybrid DVR can access 8-channel high definition network camera, video recording and decoding resolution support 1280x720, display resolution supports 1280 x 1024. Support 8 bit SATA disk, built-in storage capacity can be configured, if equipped with eight 1TB hard drive, configure the 3Mbps bitrate, then each channelAverage saving cycle is approximately 780 hours.

Prospect

"Let us see more clearly" is a high definition monitor.

Different industries, different occasions on image clarity of requirements, such as in a busy downtown to see a person's facial features, see vehicle licence is important; in high-rise buildings, crowded Hall of noisy entrances, parking lot entrances, highway, stadiums, arenas, HD monitor you can greatly enhance the value of the system.