Analysis and Comparison of Automatic Image Focusing Algorithms in Digital Image Processing

Abstract

AbstractThe selection of image focus discrimination function is the basis for obtaining high-quality images in automatic image scene measurement. The performance of several digital image processing algorithms for automatic image focus discrimination is compared comprehensively, and the calculation speed, uniqueness, accuracy and sensitivity of different algorithms are analyzed quantitatively. Firstly, this paper briefly summarizes the imaging principle and focusing principle of digital image processing automatic image focusing, and then from the image information entropy function, gray gradient function, frequency domain evaluation function, and other evaluation functions. Finally, the area selection and focus search algorithm of digital image processing window are described from the aspects of depth of field and focal depth, algorithm selection and algorithm improvement direction. The above analysis results of the characteristics of image focusing discriminant function have guiding significance for the automatic focusing control required by image automatic measurement.KeywordsDigital image processingAuto focusAutomatic image measurementEvaluation functionFocus function