Color digital camera white balance correction method based on color adaptation model

Abstract

The invention discloses a color digital camera white balance correction method based on a color adaptation model. According to the method, a color correction matrix is calculated through adoption of a root-polynomial regression method, so device related response values RGB under a plurality of common light sources (hereinafter called the correction light sources) are converted into CIE1931 tristimulus values XYZ unrelated to devices under the same light source. RGB response values of an unknown light source (hereinafter called a test light source) in a practical scene are converted into an XYZ color space through utilization of a pre-calibrated color correction matrix, the corresponding colors of the RGB response values under a reference light source are calculated through utilization of a CAT02 color adaptation model, and the corresponding colors are the colors sensed by a visual system after an observer carries out color adaptation to the test light source.

Description

technical field [0001] The invention relates to a method for adjusting the white balance correction result of a color digital camera by using a color adaptation model. The method can enable the color digital camera to realize color restoration more in line with human perception for shooting scenes. Background technique [0002] The same object often has different colorimetric parameters under different light sources. Due to the color constancy of the human visual system, these differences in chromaticity can be automatically compensated by the human eye and brain to a certain extent, so as to restore the "true" color of the object under different light sources. The white balance module in the image signal processing flow (ISP Pipeline) of a color digital camera corrects the color cast of objects under non-standard light sources by calculating the difference between the chromaticity of the actual light source and the chromaticity of the standard light source, thereby simulati...

AI Technical Summary

Problems solved by technology

[0004] If any lighting source, especially some light sources whose chromaticity deviates significantly from the reference white point, uses a unified reference light source as the target of white balance correction, the following disadvantages will occur to the image after white balance correction: 1) The output image is too " 2) The rendering effect of the light source on the scene atmosphere is completely suppressed; 3) Forcibly correcting the light source with serious color cast to the reference light source will increase the subsequent processing of the image signal processing process. Processing difficulty of modules (such as lens shading correction, color correction, etc.), which may even lead to image degradation

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