| 摘要 |
Interblock distortion often appears on a boundary of pixel blocks in a reproduced image produced from compressed image data. The interblock distortion is eliminated by correcting a density distribution in the reproduced image. First, an average density (Aij of a selected pixel block (Bij) is computed. Second, a standard deviation ( sigma ij) of a density distribution in the selected deviation is computed. If the standard deviation is equal to zero, correction value distributions DELTA fm, DELTA fn) along a main scanning direction and a subscanning direction are obtained. Finally, corrected density distribution (fmn) is obtained as a sum of the average density and the correction value distributions. |
