| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce a data quantity by allowing the coder to have a sub block generator, a coding means having an encoder, an edge detection means, a scanning means, an interleaving means and a variable length coder. SOLUTION: A sub-block generator 16 divides a DCT block into 4N-sets of sub-blocks of the same size. The sub-blocks given to respective coding blocks 20, 40, 60, 80 are fed to DCTs 24, 44, 64, 84, where the sub-blocks are coded into transformation coefficient data for one block and the result is fed to quantizers 26, 46, 66, 86. Each block of each transformation coefficient is quantized by the quantizer and the resulting coefficient array is sequentially given to scanners 28, 48, 68, 88. On the other hand, each of edge detectors 30, 50, 70, 90 detects an edge of a sub-object of the sub-block. A quantization coefficient of a quantized coefficient array scanned by each scanner is given selectively to a block 100 depending on the edge detection signal from each edge detector.</p> |
