| 摘要 |
PURPOSE:To reduce distortion of a picture of a flat portion by allocating bits properly. CONSTITUTION:A block processing section 1 divides digital picture data inputted to the picture coder by each block 10 comprising longitudinal 8 picture elements Xlateral 8 picture elements, in total 64 picture elements and outputs the data as picture data for each block 10. A grouping section 3 calculates a dynamic range (D range) of each of picture data of the block 10 comprising longitudinal 8 picture elements X lateral 8 picture elements, in total 64 picture elements, to obtain the sum of all the blocks of an area 12. The sums of the D ranges of picture data of all the blocks 10 belonging between the areas 12 are compared to group the area depending on the quantity of the difference or to group it into one group. The area having a larger sum of D ranges set to be a group G1 corresponds to a picture of an edge part and the area having a smaller sum of D ranges set to be a group G2 corresponds to a picture of a flat portion of the picture. |
