| 摘要 |
PURPOSE:To reduce the code amount of a high frequency signal in the case of sub band encoding. CONSTITUTION:A present frame and a reference frame are divided into macroblocks composed of (m) pieces of horizontal picture elements and (n) pieces of vertical picture elements for each band signal, and the block of a motion compensating image is selected from the reference frame and compared. Then, any one of (1) a differential value for each pixel value of both the blocks, (2) added value for each pixel value of both the blocks and (3) the original pixel value of the macroblock in the present frame is adaptively selected. Concerning the high band signal, sometimes the polarities are inverted at a present image and a reference image and in such a case, encoding more compressing the information quantity is enabled by using the added value rather than the difference value. |
