Wide dynamic camera technology is a technique used to allow the camera to see the characteristics of the image under very strong contrast. In some situations where the contrast between light and dark is too large, general cameras are limited by the sensitivity of CCD, and the captured images often have a background that is too bright or a foreground that is too dark. In response to this situation, wide dynamic technology has emerged and effectively solved this problem.
When objects in the field of view of a conventional camera need to be viewed outside the door or window under high brightness background light, the central backlight compensation (BLC) mode is usually used. It mainly relies on increasing the brightness of the central part of the field of view and decreasing the brightness of the surrounding parts to achieve the goal of seeing objects located in the central position clearly.
Backlight compensation, also known as backlight compensation, is the process of dividing the image into several different areas and exposing each area separately. In some applications, the field of view may contain a very bright area, while the included subject is surrounded by the bright field, resulting in a dim and non layered image. At this time, due to the high signal level detected by AGC, the gain of the amplifier is very low and cannot improve the brightness of the main body of the picture. When backlight compensation is introduced, the camera only detects a sub area of the entire field of view, and the working point of the AGC circuit is determined by calculating the average signal level of this area. Due to the low average level of the sub region, the AGC amplifier will have a higher gain, which increases the amplitude of the output signal and makes the main image on the monitor clearer, greatly reducing the subjective brightness difference between the background image and the main image, and improving the visibility of the entire field of view Although backlight compensation improves the brightness of the subject being photographed, the image quality may deteriorate to some extent.
And the wide dynamic technology involves exposing two times at the same time, one fast and one slow, and then synthesizing them to make it possible to see both bright and dark objects on the screen at the same time. Although both are measures taken to overcome the need to see targets clearly in strong backlight environments, backlight compensation comes at the cost of sacrificing image contrast. Therefore, in a sense, wide dynamic camera is an upgrade to backlight compensation.
