Method and device for image defogging

Abstract

The invention provides a method and a device for image defogging. The method combines a dark channel prior method and has better image defogging effects. The method includes: performing edge detection to a fogged image; blocking the fogged image to allow each image block to satisfy the condition that proportion of edge point number in the image to total pixel point number of the image block is in a preset threshold; and using the dark channel prior method to perform defogging calculation to the fogged image according to the blocks.

Description

technical field [0001] The invention relates to an image defogging method and device. Background technique [0002] The dark channel prior method is a theory summed up by He Kaiming and others by analyzing a large amount of outdoor fog-free image data, that is, in the non-sky local area of ​​most images, some pixels will always have at least one color channel with a very low value. In other words, the minimum value of the light intensity in this area is a very small number, which is the dark primary color. [0003] On the basis of statistics and analysis of a large number of outdoor images, He Kaiming and others summarized the prior knowledge of the dark channel color, and applied the prior knowledge to the process of image defogging, and achieved good results, but this method also exists insufficient. First, there are block effects and halo phenomena in this method. In the image processed by this method, a halo phenomenon will appear in areas with large color difference...

AI Technical Summary

Problems solved by technology

Second, the choice of scale parameters

However, after a lot of experiments, it is found that the calculated dark channel values ​​will be different if the scale parameters are different.

As an important value in the algorithm, the dark channel value will directly affect the calculation of the estimated transmittance value, which will ultimately affect the quality of the image after defogging

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