For video surveillance, image clarity is undoubtedly the most critical feature. The clearer the image, the more obvious the details, the better the viewing experience, and the higher the accuracy of applications such as intelligence. So image clarity is the eternal pursuit of video surveillance.

The standard for measuring image clarity is resolution, and the unit is pixels. The larger the value, the sharper the image. The so-called high-definition and standard-definition, the difference is reflected here. The dividing line between the two is megapixels or 720p, and those that reach megapixels or 720p are high definition. Based on such standards, CIF and D1, which currently dominate the video surveillance market, are all standard definition.

Whether it is from the perspective of resolution, display effect or smoothness, HD is more advantageous than SD. From the perspective of resolution, the resolution of 720p is 9 times that of CIF, and the resolution of 1080i / 1080p is 20 times that of CIF. Under the same display environment, HD will be much clearer. From the perspective of display effects, HD supports both large-screen display and 16: 9 wide-screen display, which can greatly enhance the user's viewing experience. In terms of fluency, HD supports higher frame rates. For example, 720p and 1080i / 1080p can support 60 frames / second or 60 fields / second, and the image fluency is twice as high as standard definition. Therefore, high-definition surveillance will inevitably replace standard-definition surveillance.