Automatic exposure control method for digital photographic device

Abstract

The invention discloses an automatic exposure control method for a digital photographic device. According to the automatic exposure control method, a partitioning counted brightness weight model corresponding to a photographing application scenario of the digital photographic device, the target brightness of a target frame image of the photographing application scenario and an exposure curved line corresponding to the photographing application scenario are selected, and the brightness of a current image is calculated in a partitioned mode; then, the average brightness of whole images is calculated, an environment photometry compensation coefficient is determined according to the average brightness, a difference value Delta Bv between the brightness of an image of a current frame and the target brightness serves as an adjustment condition, and the exposure time and an aperture value of a next frame are determined. According to the automatic exposure control method, image brightness estimation is carried out in the manner of adjusting different weight coefficients in a self-adaptation mode according to different scenarios and different collection targets, and photographing scenarios in actual application can be represented better; under the condition of not increasing the software cost and the hardware cost, accurate control over automatic exposure is achieved through simple calculation, and the photographing quality can be effectively improved.

Description

technical field [0001] The invention relates to an automatic exposure control method of a digital camera. Background technique [0002] Automatic exposure affects the basic brightness information of the image and video captured by the camera device, which is an important performance index slightly inferior to the resolution. Therefore, the research on automatic exposure control methods has important practical significance and market value. [0003] The brightness of the image video captured by the camera device is mainly determined by the following factors: the simulation of the sensor (sensor) hardware, the amplification factor of the digital circuit, the luminous flux captured by the sensor, and the exposure duration. A simple quantitative formula can be described as follows: [0004] Ev = Av + ​​Tv = Bv + Sv – Cv (1) [0005] Among them, Av represents the influence of the aperture of the camera device on the image, and Tv represents the shutter speed, that is, the expo...

AI Technical Summary

Problems solved by technology

[0015] The existing automatic exposure control technology cannot meet the changes of multiple scenes in terms of accurate control, and the application range of the camera device is very large, and the existing automatic exposure control algorithm is mostly based on the difference between the target brightness and the current brightness. The adjustment direction and characteristics of EV are chosen according to the designer's preference, and the consideration of sensor and lens characteristics is lacking.

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