| 摘要 |
<p>PURPOSE:To generate a table with the less kinds of input data by obtaining variable length code table data based on statistic data for which the statistic data in consideration of a distortion mount are accumulated for respective syncs. CONSTITUTION:After the input data are shuffled in a circuit 21, coefficient data are quantized and compressed by a DCT circuit 22, a quantization control circuit 23 and a quantization circuit 24 for constituting a compression part. Compressed data are expanded in an inverse quantization circuit 25 and an IDCT circuit 26 for constituting an expansion part, the compressed data and expanded data are compared, the distortion amount after compression/expansion is detected by a distortion amount detection means 28, multiplied with the statistic data from the quantization circuit 24 in a multiplier 29 and supplied to a table generation circuit 30 and a variable length code table based on the statistic data and distortion amount data is generated. At this time, the table for obtaining codes from sizes based on the data for which multiplied results are accumulated for the fixed period of time is generated. Thus, the variable length code table can be generated with the less kinds of the input data.</p> |
