Automatic exposure method and apparatus

Abstract

The invention discloses an automatic exposure method and a device thereof. When detecting that a moving object occurs in an image, the camera of the invention can adjust the exposure control fundamental parameters according to brightness information of the region where the moving object locates and expose the whole image according to the adjusted exposure control fundamental parameters, thus ensuring suitable brightness of the moving object region in the image, increasing the contrast and signal-to-noise ratio of the moving object region, avoiding over-darkness or over-exposure of the moving object region; simultaneously, ensuring acceptable brightness of the whole image region. Particularly, in conditions of over-weak or over-bright light, the moving object region in the image obtained by the automatic exposure method of the invention has suitable brightness, thus increasing the contrast and signal-to-noise ratio of the moving region and ensuring latter processes, such as movement tracking and moving object identification.

Description

technical field [0001] The invention relates to image acquisition technology, in particular to an automatic exposure method and device. Background technique [0002] For different application scenarios, the camera is required to have different functions. For cameras used for motion detection, scene monitoring, etc., it is necessary to perform exposure processing on moving objects called foreground (such as moving people, moving objects, moving vehicles, etc.) and background areas that remain unchanged. [0003] At present, in application scenarios such as motion detection and scene monitoring, the camera uses the exposure setting for the whole image to perform automatic exposure processing. Due to the difference in ambient light, the existing exposure settings for the entire image can make the entire image have a suitable average brightness. However, if the moving target is located in the dark or bright area of ​​the image, especially if there are windows or strong light so...

AI Technical Summary

Problems solved by technology

Due to the difference in ambient light, the existing exposure settings for the entire image can make the entire image have a suitable average brightness. However, if the moving target is located in the dark or bright area of ​​the image, especially if there are windows or strong light sources in the shooting scene or At night, etc., according to the existing camera automatic exposure method, the brightness of the moving target may be very low or very high, which will reduce the contrast and signal-to-noise ratio of the moving target, which will greatly improve the performance of subsequent video analysis, video retrieval, and moving target recognition. and other applications increase the difficulty

[0004] We know that in surveillance applications, people are most concerned about the clarity of moving objects, and it is easy to happen when there are windows or strong light sources in the shooting scene or at night, so use the existing exposure settings for the whole image to perform automatic exposure However, it is bound to cause inappropriate brightness of the most concerned moving target due to inappropriate exposure of the moving target, thereby reducing the contrast and signal-to-noise ratio of the moving target area, thus seriously affecting the follow-up video analysis, moving target Identification and other applications

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