| 摘要 |
PURPOSE:To provide the picture coder in which a picture to be coded even in the case of a photographic picture or a character picture is coded in an excellent way and the picture is coded in response to a characteristic of the picture especially even when a level difference of an edge is small like a color picture or a very small edge is overlapped on a block border. CONSTITUTION:A 1-block extract section 1 extracts a picture element block from a received picture signal. An area discrimination section 5 discriminates whether an extracted picture element block is a photographic picture or a character picture based on a characteristic quantity such as variance information, histogram information and dynamic range information. When the picture element block is the photographic block, the picture element block is subject to transformation coding by a transformation coding section 3. When the picture element block is a character picture element, a block approximation coding section 4 applies block approximation coding to the picture element block. |
