| 摘要 |
An image processor performs error diffusion by thresholding an incoming gray pixel to black or white, comparing the difference between the black or white print value and the incoming pixel gray level and superimposing the difference on the next pixel gray level. The threshold value is read out from a threshold matrix which has been modulated with a pattern which is complementary to the known artifact pattern of the error diffusion process. Typically, the threshold matrix has sparce threshold values along one of its diagonals, the direction of the diagonal being perpendicular to the prevailing direction of artifacts generated by the error diffusion algorithm.
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