| 摘要 |
A video data stream is divided ( 11 ) into blocks. First quantization scales Q arc determined ( 17, 19 ) for respective ones of the blocks, so that the quantization scales Q are sufficiently large to realize a predetermined compression rate. Subsequently it is determined ( 17, 19 ) whether there is a second quantization scale Q' that is larger than the first quantization scale Q for that at least one of the blocks and that results in a distortion of the at least one of the blocks that is less than or substantially equal to the distortion realized with the first quantization scale Q for the at least one of the blocks. The digital data stream is encoded ( 12, 13, 14 ) using the second quantization scale Q' for the at least one of the blocks when said second quantization scale Q' exists. |
