| 摘要 |
PURPOSE:To provide a picture coder in which the compression efficiency is improved when picture data are coded hierarchically and the deterioration in the picture quality is reduced. CONSTITUTION:An additional code representing a characteristic of a quantizer is omitted by deciding a quantization step width of lower layer data whose resolution is higher than that of higher layer data based on a quantization step width decided by the higher layer data whose resolution is lower for each prescribed block of layer data D31, D32, D33, D34, D35, and the compression efficiency for layer coding is improved by the omission and the deterioration in the picture quality is reduced in the picture coder 40. |
