Analysis of megapixel HD camera

Traditional analog cameras can not meet the needs of high-definition image acquisition, and high-definition has become the mainstream of video surveillance. To achieve high-definition video surveillance, high-definition cameras are indispensable. Therefore, megapixel high-definition network camera products came into being. In this paper, the principle and imaging effect of megapixel HD camera under qiao'an monitoring are simply analyzed.

Megapixel HD camera refers to the HD camera transmitted over IP network. Taking the formation of ordinary HD network camera as an example, it includes lens, infrared cut-off filter, image sensor, clock synchronization and image processing coding and compression motherboard, power supply and i/o network interface board from front to back.

Among all the forming components, the most important one is the image sensor. Whether its indicators are good or not directly affects the picture consequences of the high-definition network camera. At present, most high-definition network cameras in the market use CMOS as the photosensitive element, but compared with CCD sensor, it has the advantage in the application of high-definition network cameras.

At present, pinhole cameras and megapixel cameras are just a general term for high-definition network cameras in the industry, generally referring to high-definition cameras with millions of pixels or more. However, the industry has not yet formed a coherent scale to define the relationship between megapixel and high-definition. The so-called megapixel means that the number of effective pixels of the sensor applied to the network camera reaches more than one million, and at the same time, the field picture resolution output by the HD camera is at least 1280 × 720. Today's mainstream 1.3 million pixels, 2million pixels, or even 5million pixels higher are all megapixel network cameras, and the output image resolution is normally at least 720p or 1080p.

According to the recognized standards of the current industry, it is the most basic requirement for the video picture resolution to reach 720p as HD. Some places even call it quasi HD. In a strict sense, 1280 × 720 has not yet reached megapixel resolution. The video resolution of the generally recognized real HD image needs to reach 1920 × 1080, commonly known as 1080p.

From the above-mentioned video picture discrimination rate, we can see that the video picture provided by the megapixel HD camera can not be compared with that of the traditional imitation camera. The improvement of definition and the expansion of image field of vision are its most prominent advantages.

The picture resolution provided by the megapixel HD camera is several times higher than that of the traditional camera. In addition to the high definition of video picture, there is also a very important requirement in practical application, that is, the real-time performance of video picture. In terms of PAL system, it needs to reach the transmission and playback frame rate of 25 frames / second.

In the practical application of the industry, customers often have very clear monitoring needs and objectives to be achieved. For example, if the bank teller monitors, it is necessary to clearly see the face of each person who comes to handle business; For traffic path monitoring, it is necessary to clearly see the license plate number of vehicles passing through each lane. In order to meet these special needs, using the traditional non HD monitoring method, it is often necessary to install a camera for each teller and each lane, in order to narrow the monitoring line of sight and ensure the clarity of the monitoring target.

After the application of megapixel HD cameras, one megapixel HD camera can be used to replace multiple non HD cameras, and the monitoring effect can be achieved by using multiple traditional cameras at the same time.

The emergence of megapixel high-definition cameras has undoubtedly brought great convenience to broad-minded users, and greatly improved the quality of security monitoring. At the same time, it has been accelerating the withdrawal of traditional imitation cameras from the market.