Image definition evaluation method, automatic focusing method and corresponding devices

Abstract

The embodiment of the invention relates to an image definition evaluation method, an automatic focusing method and corresponding devices which are used for solving a problem that an image definition evaluation method in the prior art cannot adaptively improve the properties such as peak and monotonicity of an image definition evaluation function. According to the invention, the value range of a mapping relation between a brightness value and a definition evaluation value of each initial detail block can be determined in an adaptive manner according to the brightness value and the definition evaluation value of each initial detail block under different external illumination brightness in each scene; when automatic focusing is required to be performed, at least one brightness range value corresponding to each sub-block is determined according to the predetermined value range of the mapping relation and a current definition evaluation value of the sub-block, whether the current sub-block is a evaluation detail block or not is judged according to a current brightness value corresponding to the sub-block, and different weights are respectively given to evaluation detail blocks and non evaluation detail blocks, so that the interference such as noise and brightness can be eliminated, and adaptive improvement for the properties such as the peak and monotonicity of the image definition evaluation function is realized.

Description

technical field [0001] The invention relates to the field of automatic focusing, in particular to an evaluation method for image clarity, an automatic focusing method and a corresponding device. Background technique [0002] With the appearance and improvement of the automatic focusing method based on image processing, it has gradually replaced the traditional focusing method, especially in the field of cameras, becoming the most important focusing method. For automatic focusing based on picture processing, it is based on the optical picture of the target to be measured, first collect its digital picture; then judge the clarity of the picture through a certain picture evaluation function; then rely on some adjustment Focus search control strategy, control lens. [0003] Based on the above working method, there are three very important core issues in automatic focusing: evaluation of image clarity, selection of focusing window and focusing search control strategy. Among the...

AI Technical Summary

Problems solved by technology

[0005] The present invention provides an image definition evaluation method, an automatic focusing method and a corresponding device, which are used to solve the image definition evaluation method in the prior art, which cannot self-adaptively improve the sharpness and monotonicity of the image definition evaluation function etc.

Images