| 摘要 |
PURPOSE:To provide the encoder for video signal fixing the coding data length without deteriorating picture quality on the decoder side and hardly allowing the distortion caused by interrupting the transmission to be detected visually in the case the code length of the data to be transmitted is fixed. CONSTITUTION:The number of quantization bits in a quantization circuit 4 is determined based on the activity index of video block and the data length after encoding at a variable length coder 5 or based on the activity index and the number of events of the video block. Taking a certain optional video block for instance, each video block is shuffled so as to make a unit to which the video block near the circuit 4 belongs different from a unit to which the aimed video block belongs, then the video signal is compressed and encoded. In compressing and encoding each video block, the encoding is performed gradually extending from the block at the center of the screen to the ones at the peripheral section. |
