| 摘要 |
PURPOSE:To erase the picture distortion of a boundary part by executing encoding/decoding twice concerning the overlapped part of an area until the next block of the said area can be forecasted after the processing of a series of extrapolation forecasting - descrete sign conversion encoding/decoding is finished. CONSTITUTION:A vertical address generator 24 is provided to generate the vertical address of a picture memory 1 and a horizontal address generator 25 is provided to generate the horizontal address of the picture memory 1. Then, an extrapolation forecasting - descrete sign conversion encoder/decoder 27 and a selector 26 are provided. The state of a counter in the horizontal address generator 25 is increased so that the processing can be continued even when areas [1], [2] and [3] respectively exceed the left ends of areas [2], [3] and [4], and the overlapped parts of the respective areas [1]-[4] are encoded twice. By executing decoding in the same order as this encoding, for example, the left end of the area [2] is overwritten by the picture elements in the right end of the area [2] and the discontinuous distortion is canceled. |
