What is the number of lines of the camera?

Everyone knows that the camera is used in daily use. If you ask what is the number of lines of the camera, do you know? In the last round, we compared the current video surveillance field to the chaos of the end of the Eastern Han Dynasty. The current industry is mixed with dragons and snakes. The security manufacturers are mixed. Some manufacturers' descriptions of products are easy to cause confusion. 600 lines, 700 lines, 1000 lines, even 1200 lines, D1, 960H, 720P, 1080P, some friends were stunned by these concepts. Before we can count the length of each HD standard, we still need to explain some common parameters in the field of video surveillance.

What is the number of lines of the camera?

First of all, let's talk about the concept of "line", TVL (TV Line), also known as "TV line." Analog TVs use line scanning, while lines are used to indicate the resolution of the TV in the horizontal direction. As shown in the orange circle logo in the test card above, if the number of lines of the TV can reach 600 lines, it means that we can clearly see the black and white lines in the orange circle in the picture.

Similarly, the number of lines is also used to represent the resolving power of the analog camera in the horizontal direction. However, at present, the identification manners of the number of camera lines by various manufacturers are inconsistent, and are identified according to the maximum number of lines claimed by the processing chip, which are identified according to the number of pixels of the image sensor, and are also identified according to the number of lines obtained by the test. Personally feel that the actual number of lines obtained by the test is more reliable, no matter what the number of lines of the camera is nominal, the actual measurement will know how the resolution of the camera is.

The test card shown above allows the test card to fill the entire camera's shooting picture. The black and white lines can clearly distinguish the number of lines that the camera can reach. Most analog cameras have 500 lines, and some do better to 600 to 700 lines.