| 摘要 |
PURPOSE:To improve the compression efficiency and to reduce the deterioration in the picture quality when picture data are coded hierarchically by discriminating block activity as to all blocks of layer data except highest layer data whose resolution is lowest every time and selecting the processing of the layer data in the block accordingly CONSTITUTION:Input picture data D31 comprising a still picture are divided into five layers through hierarchical coding and lowermost layer data and four inter-layer differential data D40-D43 obtained as the result are coded. The inter- layer differential data D40-D43 are inputted respectively to division control circuits 50-53. The division control circuits 50-53 discriminate a threshold level of block activity representing whether or not a predetermined block in the inter-layer differential data D40-D43 is a flat block every time as to each block of the inter-layer differential data D40-D43 and decides the processing as to whether or not the corresponding block of the inter-layer differential data D40-D43 is to be sent. |
