| 摘要 |
<p>PURPOSE:To efficiently transmit pictures with satisfactory picture quality by calculating the sum of the power of a transformation coefficient to a prescribed block form the head to of the block after discrete cosine transformation, comparing it with a threshold value, judging it for the unit of the block whether block data is significant or not, and preventing the non-significant block from being transmitted. CONSTITUTION:A picture data encoder circuit 28 exerts discrete cosine transformation encoding upon a digital video signal S21 for every unit blocks Y00, Y01, Y10, Y11, Cb and Cr. Then, an inter-frame/in-frame encoding control unit 30 calculates the power of the block according to a transformation coefficient Coeff(i) from a head i=1 of the said block, to which discrete cosine transformation encoding is executed, to the prescribed block (i=1). Then, a threshold control unit 35 compares the power with the prescribed threshold value. Afterwards, the unit block Y00, (Y01, Y10, Y11, Cb or Cr) exceeding the threshold value is decided as the significant block and transmitted, and the unit block Y00, (Y01, Y10, Y11Cb or Cr) not exceeding the threshold value is decided as the non-significant block and prevented form being transmitted.</p> |
