How to solve the backlight problem of the camera

When using the camera, I often encounter the problem of backlighting. Then the focus of this article is to introduce how to solve the backlight problem of the camera. The camera plays a vital role in today's society, then we come across How to solve the backlight problem of the camera?

When installing the camera at the entrance and exit, the biggest problem is that due to the improper installation position of the camera, there will be backlighting on the monitor screen. In this regard, the author believes that there are three ways to improve it: First, avoid direct sunlight in the installation position; The second is to select a camera with corresponding improvement function; the third is to reduce the contrast with the outdoor light by increasing the illumination of the indoor light source.

(1) by adjusting the installation position

Improve the backlight phenomenon By adjusting the installation position of the entrance and exit camera, try to avoid direct sunlight from the outside, which can greatly improve the backlighting of the entrance and exit. For example, Shanghai Huating Hotel installed a camera on the two sides of the entrance and exit of the hall to monitor the access. Personnel; ICBC Shanghai Branch will monitor the camera of the entrance and exit, so that the lens of the camera is facing the person who walks out of the outlet (in the case of serious backlighting, the installation method is better than installing the camera opposite the entrance and exit, but the effect is better, but it should be caused Note that if the above flip-chip method is adopted, if there are more than 2 entrances and exits on one dot, the installation direction of the camera should be the same, otherwise there will be a protection loophole). They all solve the problem of backlighting better. There are many outlets now, the business hall is not large in size, and some entrances and exits are cash counter areas. There are not many locations for camera installation. In this case, we need to pay attention to solve the installation location problem and try to avoid The camera is installed at the entrance and exit. We say that the camera is installed at the entrance. It does not specify which position the camera for monitoring the entrance and exit must be installed. It should be important to see the effect and see the physical quality.

(2) By selecting a camera with the corresponding function

Improving Backlighting The use of hyperdynamic cameras or cameras with background compensation is also a way to improve the backlighting of the entrance and exit. Generally, the camera has AGC (Automatic Gain Control) function, that is, there is a strong and weak signal to automatically increase the internal amplification gain of the camera, and the strong signal automatically reduces the internal amplifier gain of the camera, so that the final output signal does not change substantially with the change of the input signal, and the output The signal amplitude remains basically the same, but the automatic adjustment function of the general camera is limited. Once a strong signal (such as a strong backlight) occurs, the amplifier is saturated. Without automatic adjustment, a white spot with blurred edges (backlighting phenomenon) appears on the monitor screen. The super dynamic camera automatically adjusts to a larger range than a normal camera. We can feel through practice that when a target object with a rich picture level appears in the scene, when the target object is taken by an ordinary camera, the obtained picture has many levels, so the problem of backlighting with a large contrast of the super-motion camera is selected. Can also play a certain improvement role. The backlighting phenomenon at the entrance and exit is often a very bright background and a very dark foreground target in the scene, and the position of the background and the target remains basically unchanged. The camera with BLC function (backlight compensation function) can be used only. An area is averaged to determine the AGC operating point. If the foreground target is located in the area, the clarity of the foreground target is expected to increase.