| 主权项 |
1. A method for image decolorization, comprising:
splitting an input color image having a plurality of pixels into a red image, a green image and a blue image; performing wavelet transform for the red image, the green image and the blue image to obtain a red wavelet coefficient, a green wavelet coefficient, and a blue wavelet coefficient respectively for each pixel, wherein each of the red wavelet coefficients, the green wavelet coefficients and the blue wavelet coefficients comprises a magnitude and a sign; for each pixel, categorizing the magnitudes of the red wavelet coefficient, the green wavelet coefficient, and the blue wavelet coefficient into a first magnitude ML, a second magnitude MM, and a third magnitude MS, wherein the first magnitude is larger than or equal to the second magnitude, and the second magnitude is larger than or equal to the third magnitude; for each pixel, selecting a sign of a wavelet coefficient having the first magnitude to be a sign of an enhanced wavelet coefficient; for each pixel, calculating a magnitude of the enhanced wavelet coefficient ME by the below equation:
ME=ML+(a*MM−b*MS) where a denotes a first adjusting parameter, and b denotes a second adjusting parameter; for each pixel, determining the enhanced wavelet coefficient based on the calculated magnitude of the enhanced wavelet coefficient and the selected sign of the enhanced wavelet coefficient; and applying an inverse wavelet transform to the determined enhanced wavelet coefficients to obtain an enhanced grayscale image. |
