Fremgangsmåde til kodning med variabel længde og fremgangsmåde til dekodning med variabel længde

摘要

According to the present invention, an image coding apparatus (103) that encodes quantized coefficients corresponding to an image signal as target data to be processed is provided with a run-length encoding unit (RLE2) that assigns variable length codes to the quantized coefficients using code tables. The run-length encoding unit (RLE2) forms a second code table by optimizing a first code table to the target data to be processed, and selects one of the first and the second code tables as a code table that is to be employed for the assignment of the variable length codes in accordance with a quantization parameter (QP) or a variable length coding selection signal (VlcSel), whereby redundancy of information included in the target data to be processed can be effectively eliminated, and the compression ratio for the image signal or the like can be further increased.