When high-brightness areas and shadows, backlights, and other relatively low-brightness areas under the strong light source coexist in the image, the image output by the camera will make bright areas white due to overexposure, and dark areas black due to underexposure , Which seriously affects the image quality. Wide dynamic is a technology applied to make the particularly bright and dark parts in the scene can be seen clearly at the same time. 

Wide dynamic is to expose twice at the same time, once fast and once slow, and then synthesize so that the bright and dark objects on the screen can be seen clearly. The application scenario of WDR technology is similar to backlight compensation. WDR technology uses two exposures of the sensor to obtain two images that can be seen clearly in the foreground and the background, and then superimpose the images. WDR is not suitable for scenes with fast moving objects.