| 摘要 |
<p>PURPOSE:To compress data efficiently with respect to the coder and its method applying 2-dimensional orthogonal transformation to picture data and coding the data. CONSTITUTION:The coder is provided with a quantization circuit generating section 1, a DC block detection section 3 detecting a DC block whose AC component quantization coefficient is all zero, a coding procedure decision section 4 calculating an evaluation figure based on a DC block number or its consecutive length and deciding the division coding of a variable length coding by a DC component only and a variable length coding of an AC component only as to one pattern based on the DC block number or the evaluation figure or consecutive variable length coding of the DC component and the AC component for each block or non-division coding, and a variable length coding section 5 applying variable length coding to a quantization coefficient according to the coding procedure decided by the coding procedure decision section 4.</p> |
