| 摘要 |
PURPOSE:To improve the coding efficiency by implementing encoding with adaptive bit allocation corresponding to the sets of subblocks resulting from division and using the result of coding as a variable encoding output. CONSTITUTION:A dividing means 1 divides either or both of frequency and time, and the dividing means 1 divides the block of a prescribed length into subblocks. The division number in this case forms the sets of different subblocks and an encoding section 2 applies coding at every set by the allocation of an adaptive bit. An evaluation section 3 obtains an evaluation function based on the result of encoding at every set of subblocks and selects a set of subblocks with a best evaluation function, and when, e.g. quantization noise power is used as the evaluation function, a set of the subblocks minimizing the quantization noise power is selected. Thus, the variable length code is obtained based on optimum bit allocation according to the optimum division number of subblocks corresponding to the change in a signal power in the block. Thus, the encoding processing efficiency is improved. |
