| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a coder with a high coding efficiency. SOLUTION: A received image signal s10 is given to a discrete cosine transformation(DCT) means 21 and a wavelet transformation (WLT) means 11 and outputted to a code quantity comparison means 15 via 1st and 2nd scanning means 22, 12 connecting respectively to the DCT means 21 and the WLT means 11, 1st and 2nd quantization means 23, 13, and 1st and 2nd coding means 24, 14. The code quantity comparison means 15 compares the code quantities converted and coded by the various conversion means and outputted from the 1st and 2nd coding means 24, 14. A changeover switch 16 is used to connect either of the outputs of the 1st and 2nd coding means 24, 14 which has a smaller code quantity to an external terminal, from which the resulting code is outputted.</p> |
