| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a moving image encoder capable of efficiently controlling a code amount generated in encoding complicated images and the images under rapid movement and improving the image quality of decoding images. SOLUTION: A frequency conversion means 104 performs frequency conversion, a band limiting means 2 executes a band limiting processing and a quantization means 105 performs quantization. In this case, a quantization width obtained from a quantization width control means 3 is multiplied to a quantization matrix and division by the matrix value is performed. The quantization width is decided by a generation code amount obtained by a code amount observation means 4. A variable length encoding means 106 executes variable length encoding, an output buffer memory 107 mitigates the difference of data amounts for the respective images and outputs an encoded bit stream and the generation code amount is observed by the code amount observation means 4 for the output of the variable length encoding means 106. Thus, the quantization width in quantizing is decided by the quantization width control means 3 and the ratio of the band limiting processing in the band limiting means 2 is decided.</p> |
