color space is proposed to solve the problem of chrominance distortion and details lost caused by image saturation. Neighborhood's chrominances are used to correct the saturated pixel
and the unsaturated channel information of the pixel is used as a reference. The calibration point is located on the extension line of the original saturated straight
and has the shortest distance between the extension line and the line formed from weighted average of its neighborhood's chrominances
when 1-channel saturated pixels are corrected. Since the correction is performed in the YC
b
C
r
three-dimensional color space
the luminance of the corrected pixels can be fixed
simultaneously. The chrominance of the saturated pixel is restored by the correlation of neighborhood chrominance
and the luminance of the saturated pixel is restored by computing original values of unsaturated channels
when 2-channel saturated pixels are corrected. The neighborhood recovery method is used to the chrominance of the saturated pixels
and the gradient maintenance procedure is employed to the luminance of the saturated pixels
when 3-channel saturated pixels are corrected. Experimental results show that the method is more effective in correcting chrominance and luminance of both RAW images and processed images
and maintains the image information of the unsaturated area as much as possible.
关键词
Keywords
references
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