| 摘要 |
PROBLEM TO BE SOLVED: To reduce an encoded data amount to be transmitted by adaptively significance-judging motion compensation residual signals and to control the encoded data amount to be transmitted to be fixed at all times by performing feedback/feedforward buffering. SOLUTION: As for input image data, motion vector is detected by a block unit by block matching for instance with the locally decoded images of a frames in the past. By the motion vector of the block unit, motion compensation is performed to a previous frame, predicted pictures are prepared and a predicted residual with the input image data is calculated. A target bit rate is reset from a bit rate and the buffer residual amount of a framing circuit 17 serving also as a buffer, and for the predicted residual, respective hierarchical branches are predictively calculated beforehand and the hierarchical branch to be the reset target bit rate is selected. Significance judgement is performed for the hierarchical branch, quantization is performed, then variable length encoding is performed and the encoded data mount is transmitted through the framing circuit 17 serving also as the buffer. |
