| 摘要 |
<p>PURPOSE:To reduce circuitry by decreasing a code amount estimating circuit in the case of deciding any optimum quantizer concerning the device and method for encoding digital image signals to encode, record and reproduce video signals with high efficiency by DCT transformation. CONSTITUTION:Spectrum data are fetched into a buffer memory 52, and any optimum quantizer is roughly decided by a quantizer deciding circuit 54 corresponding to the outputs of code amount estimating circuits 53-3, 53-7 and 53-11. Then, quantizers corresponding to code amount estimating circuits 56-k, 56-k+1 and 56-k+2 are selected by the output of the quantizer deciding circuit 54. Next, spectrum data are fetched into a buffer memory 57, and any optimum quantizer is decided by a quantizer deciding circuit 55 corresponding to the outputs of code amount estimating circuits 56-k, 56-k+1 and 56-k+2 in the second stage. Thus, since the quantizer is decided over two stages, the number of steps for code amount estimating circuits can be decreased.</p> |
