| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an image coding apparatus and method in which image quality will not occur in a rapidly changing transient state, even if a complicated image rapidly changes into image of simple contents or in the reverse case. <P>SOLUTION: An encoder 20 comprises a VBR control unit 22 for determining the quantization (Q) scale VBRq of a VBR (variable bit rate); a maximum CBR control unit 23A for determining the Q scale CBRmaxq of a maximum CBR (fixed bit rate); a minimum CBR control unit 23B for determining the Q scale CBRminq of a minimum CBR; and a quantization scale comparison unit 25. In the quantization scale comparison unit 25, VBRq and CBRmaxq are first compared to select the greater one, and the selected greater one and CBRminq are then compared, to select the smaller one. An image compression-coding unit 24 performs coding, using the quantization scale QSC selected in the quantization scale comparison unit 25. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
