| 摘要 |
A method for contrast enhancement for digital images, including filtering an original image having original color values, to generate a first filtered image corresponding to bright color values, and a second filtered image corresponding to dark color values, deriving local highlight multipliers by applying a highlight response curve to the first filtered image, the highlight response curve being a function of color value that increases from a response value of one, corresponding to a color value of zero, to a response value greater than one, corresponding to a maximum color value, deriving local shadow multipliers by applying a shadow response curve to the second filtered image, the shadow response curve being a function of color value that decreases from a response value greater than one, corresponding to a color value of zero, to a response value of one, corresponding to a maximum color value, deriving local offset values by applying an offset curve to the first filtered image, and processing the original image, including subtracting the local offset values from the original color values to generate shifted color values, multiplying the shifted color values by the local highlight multipliers, and further multiplying the shifted color values by the local shadow multipliers, thereby generating a contrast-enhanced image from the original image. A system and a computer-readable storage medium are also described.
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