Surveillance cameras expand seven functions

The video surveillance business has a long history and is traditionally widely used in the field of security. It is an important means to assist the public security department in cracking down on crimes and maintaining social stability. In recent years, with the popularization of broadband, the development of computer technology, and the improvement of image processing technology, video surveillance has become more and more widespread in education, government, entertainment, medical care, hotels, sports and other various fields.

First, video surveillance needs expansion

Remote network video surveillance system represented by network video server. The network video server solves the problem of video stream transmission on the network. Digital processing and transmission are started from image acquisition. This makes the selection of transmission lines more diverse. As long as there are networks, it provides the possibility of image transmission. The entire system tends to be platform-based and intelligent. Many Internet companies have begun to get involved in the development of such video surveillance systems and are still at the initial stage of the market.

The scope of traditional video surveillance services is very narrow, both in terms of geographic coverage and user group coverage. This year, the development of video surveillance platforms shows some characteristics that are different from the past, gradually extending to large areas and multi-fields, with a wider range of applications. More comprehensive.

(I) From individual industries to multiple areas

In the past, China's video surveillance applications mainly concentrated in government departments and financial, public security, transportation, electricity and other special departments and industries. Among them, the government sector and the financial industry accounted for 20.9% and 20.6% of the market respectively. However, with the advancement of social informationization, the demand for video surveillance in a growing number of industries and fields has increased substantially. Even traditional users such as public security have proposed new patterns and functional requirements for city surveillance in terms of “safe cities”. . This year, video surveillance began to expand from individual areas such as banking and transportation to various fields, from traditional security monitoring to management monitoring and production management.

In addition, the use of video surveillance only for the corporate industry has gradually been broken, and public households have also become new markets for video surveillance applications in 2008. In the public household market, video surveillance is mainly applied to the security of homes and the monitoring of property. The user can install the camera at home and use the home gateway as a video server. The user can remotely monitor the home security through the Internet in real time. Although it is far from the full realization of the digital home, with the development of IPv6 technology and information appliance technology and the further optimization of mobile monitoring equipment, video surveillance technology is likely to be first promoted in digital homes. A domestic market research report pointed out that as individual users attach more importance to home security, the awareness of using video surveillance systems to protect residential safety has been significantly strengthened and will become an emerging market in 2008.

(b) From local monitoring to trans-provincial inter-regional

The market for video surveillance demand continues to expand. In addition to traditional industries, enterprises and individual markets are also emerging. The most economically active small and medium-sized enterprises and individual users in China have clearly demonstrated their application prospects for video surveillance. At the same time, the requirements of users are getting higher and higher. Among them, the most prominent is the requirement to realize real-time, non-geographical, and unimpeded transmission of large amounts of video data, so as to achieve resource sharing, and to provide convenient and fast management personnel and decision makers at all levels. Effective service.

Especially for large group companies, these companies are across provinces and regions, branch offices are spread all over the country, and activities between branches are also very frequent. If people are allowed to go back and forth, it will obviously reduce work efficiency and waste. Enterprise resources increase operating costs. Through video surveillance, it is possible to realize the situation of the company in a timely and intuitive manner even in a remote place. Therefore, these customers are in urgent need of the video surveillance system that connects the entire province and even the whole country. Many large-scale enterprise groups including Haier Group are required to be capable of inter-provincial and inter-provincial expansion in the expansion of the video private network. This shows that powerful and international enterprise groups hope to increase the coverage of video surveillance systems and increase their coverage. Efficiency, reduce costs. It can be foreseen that breakthroughs in local network restrictions and the realization of intra-provincial or inter-provincial networking will be an important trend in the development of video surveillance platforms in 2008.

(c) From providing access to system integration

At present, when telecom companies in many places build video surveillance systems, they only provide network channels for users and cannot participate in terminal procurement, software installation, and operation and maintenance. In this mode, users need to purchase video terminal equipment by themselves, build information management software systems on their own, and also commission third parties to perform system and line maintenance. This not only increases the difficulty for users to use services, but also makes the effectiveness of video surveillance systems. Greatly reduced.

To this end, experts pointed out that telecom operators must become experts in informatization. When developing video surveillance services, they must use broadband networks to network discrete and independent image collection points and achieve unified monitoring and unification across regions across the globe. Storage, unified management, integrated use of industry resources; not only provide access, but also system integration, should provide integrated packaged services from hardware to software, from construction to maintenance.

Two or seven functions help boost night vision

With more and more applications of surveillance cameras, the functions and requirements of surveillance cameras on different occasions are also very different. For some special environments and special task requirements, ordinary surveillance cameras can not meet the needs, and need some special technical functions to help. For example, in the night vision, the camera's seven functions make the image more vivid and clear.

(A) WDR wide dynamic function

Speaking of the wide dynamic capabilities of surveillance cameras, this seems to be the "standard" for many cameras. The wide dynamic function is suitable for places where lighting is strongly contrasted, and particularly bright parts and particularly dark parts of the image scene can be clearly seen at the same time. Since the monitoring environment will be subject to back light, etc., it is particularly easy to cause the background to be too bright and the subject is over. Dark conditions, even when severe, make it difficult to distinguish between outlines. Wide dynamic technology is mostly applied where light and dark colors alternate.

Speaking of the wide dynamic function, one has to talk about the influence of light on the quality of the surveillance image. If the background light is too strong, the light suppression function can be used. Especially in the road bayonet, the success of capturing the license plate number depends entirely on the light suppression effect. . The backlight compensation function is similar to the wide dynamic and strong light suppression.

(B) HBLC backlight compensation is one of the highlights suppression performance

Backlight compensation (BLC) is very similar to the above two application methods. If distinguishing by function, BLC is one of the ways to achieve strong light suppression, but it is not completely included. The backlight compensation redefines the metering area to ensure correct exposure of the image and avoid silhouette phenomena in dark areas. It effectively compensates for the disadvantages of monitoring under strong light and backlight conditions, and reduces the possibility of imperfect images.

After talking about the impact of light on the monitoring, it's better to look at the surveillance under night vision environment. In the low-illumination environment, there are often many noise problems in monitoring, especially night vision color images, and the noise is unimaginable. Good noise reduction technology can solve this problem.

(3) 2D/3D digital noise reduction

The 2D/3D mentioned here is not the 3D three-dimensional image explained in the movie. Instead, the non-overlapping information is automatically filtered out by comparing several adjacent frames of the image, thereby displaying a relatively pure and delicate picture. The digital noise reduction technology is mostly used for high-resolution surveillance cameras. The 700TVL camera can make the noise reduction technology more efficient through DSP processing, and the signal-to-noise ratio will be greater than 52dB.

What are the differences between 2D and 3D noise reduction? When not yet talking about high-definition images, 2D noise reduction technology can meet the needs of most users for the image, but as people's requirements for images become higher and higher, 3D digital noise reduction appears in the original frame of noise reduction. On the other hand, noise reduction between frames and frames is added, which is the savior of analog high-definition images.

(D) high-sensitivity monitoring

Also suitable for night vision surveillance, high sensitivity cameras are the best choice for dark or low light environments. Ordinary day/night surveillance cameras will convert color images to black and white in darker environments, while high-sensitivity functions will still maintain night vision color mode, especially for night-time face capture, vehicle identification, or accidental traffic accidents Processing and so on.

Of course, such a high-definition night-vision color camera is expensive, if you do not have enough funds to purchase such a surveillance camera, you may be able to implement night vision HD in a different way.

(5) Infrared filter ICR day and night conversion

The filter can realize the function of camera color turning black. Older surveillance cameras are electronic color to black, and the new equipment is basically automatic. Automatic color to black is achieved through high-level image processing and image algorithms. Compared with traditional infrared lamps, this ICR automatic switching mode reduces the burden of infrared light, providing clear color images during the day and automatically at night. Switch to black and white mode.

(6) Sensor Improvement Scheme

In addition to the day-night conversion mode mentioned above, other innovative applications for night vision low illumination mainly focus on sensors, including low-light sensor improvements, pixel combinations, or dual-sensor applications, etc., to increase the amount of light transmitted in night vision environments, Clearer image effects.

If you do not understand the surveillance camera, then for digital cameras, the principle of using back-illuminated CMOS sensors is the same. Due to the strict process requirements, back-illuminated sensors are not widely used in surveillance cameras. Back-illuminated CMOS image sensors have a qualitative leap in photosensitivity compared to traditional CMOS sensors. In low-light environments, back-illuminated sensors are used. The high-definition camera of the CMOS sensor has a great performance improvement in focusing ability, image quality performance, image noise control, and the like.

Back-illuminated CMOS image sensors have better high-sensitivity and noise control performance in addition to excellent low-light performance. Noise is less than before and most of them adopt high-speed chips, support full HD or 60 frames of high-definition images per second. Making a fuss on the sensor becomes a shortcut to achieve high-definition picture quality.

(7) Adaptive Exposure Compensation

If you look at a surveillance camera as a digital camera, then finally we talk about exposure compensation. The exposure compensation is to control the automatic gain control and the shutter to meet the monitoring in different environments. According to the user's settings, the camera uses different or changing light.

In a video environment where the light is significantly different, generally we will use an automatic aperture camera to adjust the light ingestion to ensure the best imaging results. However, if some outdoor cameras may be exposed to the light conditions. At this time, if the aperture is repeatedly adjusted by the automatic adjustment system, not only the workload of the camera will be increased, but also the aperture motor may be burned. Therefore, this requires the support of exposure compensation wide dynamic technology.

If you are still worried about night vision surveillance, then please carefully read the above seven features of the surveillance camera to understand these can help you easily deal with night vision, low light monitoring troubles. Each of them is a good night vision monitor.