A computing and image correction method for light source color

Abstract

A light source color calculation and image correction method is provided, which relates to a calculation and correction method of a light source during the identification and analysis of color images. The method comprises the following steps: normalizing the colority of each pixel in a color image; rapidly extracting a highlight area by a voting method based on the change gradient of pixels by using pure diffuse reflection or less mirror reflection with respect to the surrounding pixels, that is, the property of large similarity degree of the pixels; deducing the linear relationship between inverse intensity and colority and the representation and correction method of the light source color based on a simplified bidirectional reflectance function illumination model, so as to respectively project the colority values of the three channels of the pixels in the highlight area to spaces defined by the inverse intensity and the colority and thus to transform a three-dimensional space into a two-dimensional space; linearly matching the points in the inverse intensity space by means of parameter approximation to obtain a colority axis intercept (that is light source color value); and performing the color correction on the normalized image based on the light source color value and then reverting to an image under standard white light conditions.

Description

technical field [0001] The invention relates to a method for calculating and correcting the color of a light source, in particular to a method for calculating and correcting a light source in the identification and analysis of color images, so as to maintain the color constancy of the image. It belongs to the field of image information processing. Background technique [0002] The performance of an object on an imaging system is determined by three aspects: illumination, surface properties of the object, and sensor performance of the imaging system. Since the color of the light source, especially in natural scenes, is generally not pure white, the color of the light source must be considered in stereo matching and object recognition. In addition, changes in the illumination of the shooting environment will lead to changes in the color of the target in the image. In order to ensure the reliability of the analysis results, it is necessary to calculate and correct the color of...

AI Technical Summary

Problems solved by technology

[0006] Technical problem: The purpose of the present invention is to solve the deficiencies of the prior art: slow speed, restrictions on texture, complex calculations, etc., to provide a method that does not require image segmentation, has no restrictions on the surface texture of objects, and performs light source color in two-dimensional space. Calculation of a light source color calculation and image correction method, and correct the image to the color under standard white light

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