An infrared image enhancement method based on a histogram

Abstract

The invention relates to an infrared image enhancement method based on a histogram, and the method comprises the steps of carrying out the blind element compensation and non-uniformity correction of 14-bit infrared image data, and then carrying out the statistics of the histogram information of an infrared image, and obtaining a statistical histogram sequence; after the effective gray level histogram sequences are determined, selecting the local maximum values of all the effective gray level histogram sequences, carrying out a duplicate removal step, ranking the remaining local maximum values,and determining a threshold value; traversing the statistical histogram sequence, and determining the gray value of the maximum value of the sequence; traversing left and right, comparing the relationship between the value of the statistical histogram corresponding to each gray value and a threshold value, and determining a step length; and carrying out the gray scale transformation in a step length t progressive increase mode. According to the present invention, the partial target information lower than the background temperature is abandoned, and the proportion of the background part occupied in the 8-bit gray scale is compressed, so that the background of the final image is relatively black, and the target is highlighted.

Description

technical field [0001] The invention relates to the technical field of image processing, in particular to a histogram-based infrared image enhancement method. Background technique [0002] With the improvement of the precision of uncooled infrared focal plane array detectors, infrared images are more and more widely used. At present, the infrared data sampled by A / D is generally 14 bits, and the 14-bit image data cannot be visualized. Therefore, it is necessary to convert the 14-bit Infrared data is compressed into 8 bits through a series of transformations. At present, in the process of converting 14-bit infrared data into 8-bit storytelling, the gray levels of small infrared targets are often relatively close. The existing technology often converts the same target into a single gray level during the conversion process and loses the details of the target. Information, if the temperature difference between the target and the background is small, it is likely to be directly ...

AI Technical Summary

Problems solved by technology

[0004] (1) Since the sky is used as the background in the scene, the local maximum value of the background part and the maximum value of the faint target part in the effective gray level histogram sequence It is often not in an order of magnitude. At this time, it is calculated by the average value of the local maximum value, and the obtained value is often too large, so that a part of the background data will be treated as details for enhancement processing, and the details cannot be accurately highlighted.

[0005] (2) The difference between the upper threshold and the lower threshold is often relatively large. According to the direct mapping of the corresponding values ​​in the cumulative histogram, there are multiple adjacent gray values ​​in the target part that will When it is mapped to the same gray value, the details of the target are not enhanced, resulting in compressed or lost gray levels

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