Image focusing measure implementation method based on local edge detection

Abstract

The invention discloses an image focusing measure implementation method based on local edge detection, and belongs to the technical field of information processing. The method comprises the followingsteps: firstly, carrying out Gaussian filtering on an image, then partitioning the filtered image, and carrying out edge detection based on a moment function on each sub-image to obtain an edge imageof the corresponding sub-image; constructing the definition of the sub-images through the edge images, and finally, solving the variance of a set formed by the definitions of all the sub-images, and taking the variance value as the focusing measure of the whole image. According to the method, on the basis of Gaussian filtering and image blocking, edge detection based on a moment function is adopted to extract image detail information, the method has the advantages of being simple in principle and low in calculation complexity, through implementation of the steps, interference of noise on the image detail information is reduced, and particularly, the noise robustness under the low-contrast imaging condition is high. The method is suitable for a passive imaging system of a camera and has high popularization and use value.

Description

technical field [0001] The invention belongs to the technical field of information processing, and in particular relates to a method for realizing image focus measurement based on local edge detection. Background technique [0002] Camera equipment in daily life, such as single-lens reflex cameras, mobile phones with camera functions, and monitoring and capture systems at intersections, can all obtain clear images. However, the acquisition of a clear image depends on the automatic focusing performance of the camera device. At present, camera equipment on the market mainly adopts automatic focusing technology of passive imaging. Its core is to design a focus measure for evaluating image clarity, select the clearest image and save it through the focus measure. Therefore, a focus measure implementation method with good performance directly affects the quality of the captured image. [0003] Currently widely used image focus measurement methods are constructed based on image ...

AI Technical Summary

Problems solved by technology

If the background of the image is relatively uniform or relatively smooth, it is very susceptible to noise at this time, so that the corresponding focus measurement cannot reflect the sharpness information of the image

For example, if you use the camera function of a mobile phone to take pictures indoors or in night scenes with relatively weak lighting conditions, we will find that the autofocus function of the (mobile phone) camera is not easy to use, and the captured images are blurred and grainy

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