Tone evaluation apparatus and tone evaluation method
AssigneeCanon Kabushiki Kaisha
InventorChiaki Kaneko
Life of this patent
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Abstract
A tone evaluation method acquires color information on the second color space of a patch image corresponding to a grid point in the first color space, and calculates as the feature amount of a color conversion table the variation of the color information between two grid points in the first color space. Then, on the basis of the feature amount, a tone evaluation value for the color conversion table is calculated. In addition, on the basis of the variation of the feature amount, a tone jump position in the color conversion table is extracted and displayed.
Claims13
A tone evaluation apparatus which evaluates a tone reproduced using a color conversion table for converting image data on a first color space into image data on a second color space, the apparatus comprising:
- an acquisition unit adapted to acquire color information on the second color space for each of a plurality of grid points in the first color space;
- a calculation unit adapted to calculate a tone evaluation value for the color conversion table on the basis of a variation of curvature indicating a bending degree of a curve of the color information between the grid points in the first color space;
- and
- an evaluation unit adapted to evaluate a tone, reproduced using the color conversion table, on the basis of the tone evaluation value.
A tone evaluation method of evaluating a tone reproduced using a color conversion table for converting image data on a first color space into image data on a second color space, the method comprising:
- an acquisition step in which a color information acquisition unit acquires color information on the second color space for each of a plurality of grid points in the first color space;
- a calculation step in which a tone evaluation value calculation unit calculates a tone evaluation value for the color conversion table on the basis of a variation of curvature indicating a bending degree of a curve of the color information between the two grid points in the first color space;
- and
- an evaluation step of evaluating a tone, reproduced using the color conversion table, on the basis of the tone evaluation value.
Dependencies are inferred from the claim text.