Image Dehazing Method Based on Sky Segmentation and Transmittance Adaptive Correction

Abstract

The invention discloses an image defogging method based on sky segmentation and self-adaptive correction of transmittance. It uses an iterative threshold segmentation algorithm to divide a foggy image into a sky area and a non-sky area, and adjusts the brightness of the divided sky area. The non-sky area is defogged using a dark channel prior algorithm based on fast bilateral filtering and third-order logarithmic polynomial correction of transmittance. At the same time, the average value of the high-brightness pixel set in the dark channel image is used to ensure that the estimation result of the atmospheric light value tends to a reasonable value; the output image is further enhanced by using the fast bilateral filter of the transmittance and the third-order logarithmic polynomial transformation, thereby achieving denoising , Edge protection, and the purpose of eliminating the halo at the edge of the scene. Experimental results show that the invention has the advantages of good defogging effect, high color fidelity in the sky area, and strong edge maintaining ability.

Description

technical field [0001] The invention relates to the field of outdoor monitoring image processing, in particular to an outdoor monitoring image defogging method based on sky segmentation and adaptive correction of transmittance, which has good defogging effect, high color fidelity in the sky area, and strong edge retention ability. Background technique [0002] In recent years, the application range of video surveillance systems has become more and more extensive, such as road monitoring, vehicle monitoring, public safety monitoring, etc. For video surveillance systems in indoor scenes, it can capture high-definition video images in most cases; for video surveillance systems in outdoor scenes, the shooting quality depends largely on the weather environment. Under fog, haze and other weather conditions, a large number of tiny water droplets and aerosols suspended in the atmosphere have a scattering effect, resulting in color distortion, contrast and visibility reduction of ima...

AI Technical Summary

Problems solved by technology

However, the transmittance map refined by guided filtering is blurry, and the edges of foreground objects are not sharp enough; and, because the dark channel value in some areas is much greater than 0, which is close to the atmospheric light value, so that using the atmospheric light curtain guided map and The transmittance calculated by the guided filter has a large deviation, and the color of the sky area is obviously distorted

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