Fog-degraded image sharpening method based on turbulent infrared radiation model

Abstract

The invention relates to a fog-degraded image sharpening method based on a turbulent infrared radiation model. The method comprises the following steps: implementing Fourier transform on an image to obtain a degraded image in the frequency domain, and further obtaining an atmospherical modulation transfer function (MTF) according to the degraded image in the frequency domain; calculating the unknown refractive index structure coefficient in the atmospherical MTF; removing the atmospherical MTF from the degraded image in the frequency domain by filtration in the frequency domain; and implementing inverse Fourier transform on the frequency domain image of which the atmospherical MTF is filtered out to obtain the image subjected to sharpening processing. According to the fog-degraded image sharpening method disclosed by the invention, the influence of atmospheric scattering on image contrast attenuation can be recovered based on the inverse process analysis of the degraded infrared image generation without increasing the hardware cost, and thus the sharpening processing problem of the fog-degraded infrared images can be solved, and relatively simple calculation and relatively high efficiency can be achieved.

Description

technical field [0001] The invention belongs to the field of image processing, and in particular relates to a foggy degraded image clearing method based on a turbulent infrared radiation model. Background technique [0002] Infrared imaging has excellent atmospheric penetration ability and night vision function, and is very sensitive to temperature changes, so it has been widely used in military defense, remote sensing detection, public health epidemic prevention, public health epidemic prevention, chemical substance detection and identification, etc. However, the radius of suspended particles in the foggy atmosphere is large, and the scattering effect of atmospheric particles makes the original low gray value of the infrared image strengthened, while the high gray value is weakened, so that the gray level distribution of the image is too concentrated , leading to poor contrast; on the other hand, in the process of mapping the image from the three-dimensional space to the tw...

AI Technical Summary

Problems solved by technology

However, the effective monitoring distance of laser or CCD sensors based on vision will be greatly shortened under such weather conditions, and cannot provide effective confirmation information for radar sensors, while sensors based on infrared can only detect thermal signals and cannot detect of non-heat-dissipating signals for efficient detection of

Therefore, this strategy has some application limitations in foggy weather conditions, and increases the cost of expensive hardware

[0005] (2) Regardless of the specific reasons for image degradation, but purely from the perspective of image processing, the problem of clearing degraded infrared images in foggy weather is essentially the problem of image contrast enhancement;

These methods rely on the depth information of the image scene, and some require too much manual intervention

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