PICTURE ENCODING SYSTEM

PURPOSE:To decrease distortion and to obtain a satisfactory decoded picture by quantizing and encoding a block, for which an outline is decided to exist. CONSTITUTION:An input picture signal is divided into the blocks, which are composed of plural picture elements, and it is detected by an outline detecting part whether a significant picture outline part exists in this block or not. Then, a direction, in which the outline in the block is traveled, is detected by an outline direction detecting part. According to a detected result, a quantizing position to be adaptive to the direction, in which the outline is traveled, is selected by a quantizing mask part 9 and a quantizing parameter to be determined by a parameter determining part 10 is sent to a quantizer 11. Then, the conversion coefficient of a discrete cosine converting part 5 is quantized. A quantized result is encoded by a variable length encoding part 12 and outputted. For the output of the quantizer 11, a sum with a motion forecasting signal from a frame memory 13 is obtained and a forecasting vector is generated by a motion compensation processing part 14. Then, the motion forecasting signal is generated.