| 摘要 |
PURPOSE: To improve the quality of a picture to be transmitted and to reduce the bit rate required for transmission by using two-dimensional spatial adjacency property so that the continuity of luminance is directly controlled between picture elements spatially close to each other in adjacent blocks. CONSTITUTION: Each picture element block obtained by a block forming stage 11 is transferred to a quantizer 12, and the most approximate value is retrieved to select a desired item (code word) from a selected specific code book. The index of the preceding code word is transferred to an inverse quantizer 13, and picture elements in a row and a column which are adjacent to or overlap the block which passes filters 24 and 26 and is in the middle of encoding appear in the state output in specific row and column states and are given to the control part of a switch 20, and the quantizer 12 controls a state code book to be used for retrieval of the most approximate value. Thus, transmission is performed with a properly low bit rate regardless of the state most suitably matched to edges of picture element blocks. |
