Automatic Dehazing Method and System for Sea Fog Images Based on Dark Channel and Retinex

Abstract

The invention discloses a sea fog image automatic defogging method and a sea fog image automatic defogging system based on a dark channel and Retinex, and belongs to the technical field of image information processing. The method comprises the following steps: (1) calculating a dark channel image of an input image; (2) calculating the proportion of the low-value pixels of the dark channel image, and calculating the brightness and contrast characteristics of the input image; (3) automatically classifying the image according to the proportion and the characteristics calculated; and (4) processing a to-be-processed image according to the category of the image. The invention further discloses a sea fog image automatic defogging system based on a dark channel and Retinex. According to the invention, an image can be classified according to the attribute of the image, and a corresponding processing method can be selected adaptively. The contrast and definition of sea fog images are improved greatly. Moreover, the algorithm has low complexity and high operation speed, and thus can be used in a maritime intelligent transportation system.

Description

technical field [0001] The invention belongs to the technical field of image information processing, in particular to a method and system for automatically defogging sea fog images based on dark channels and Retinex. Background technique [0002] The ocean accounts for about 71% of the earth's surface area, and the ocean is a treasure house of many resources. In recent years, with the reduction of land development space and resources, human beings have further extended the goal of exploration and development from land to ocean. Therefore, the issue of ocean security has become particularly important. Due to the particularity of the marine environment, monitoring is usually used to strengthen the supervision and management of marine safety. The cameras installed on marine navigation equipment such as fishing boats and ships can observe the sea surface conditions in a timely and effective manner, which is of great significance to the safety of personnel and equipment. . [0...

AI Technical Summary

Problems solved by technology

The extraction of the sea antenna can ensure that a more accurate sky area is obtained to obtain an accurate atmospheric light value, but the maximum brightness is often close to 255, so it is easy to cause the overall image to be dark after defogging

[0008] In the paper "An Improved High Efficiency Dehazing Algorithm for Maritime Targets" (published in "Journal of Dalian Maritime University", 2014, v.40; No.15904:85-88.), Xia Guilin et al. The estimation of the image has been improved. Since the sky area is most likely to be at the top of the image, the paper searches for the brightest pixels in the top 1% of the top 1 / 5 of the grayscale image of the image, and converts the original pixels corresponding to the brightest pixels in the top 1%. The average value of the RGB three-channel at the midpoint of the image is used as an estimate of the global atmospheric light A, but the top 1 / 5 of the image is not necessarily all the sky area, and the robustness of the algorithm is not strong

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