| 摘要 |
PURPOSE:To compress efficiently a mixed picture between a character and a contrast picture by discriminating a character/line picture area or a contrast picture depending on the probability of generation of white/black pattern data comprising plural picture elements, separating the areas and applying MH coding to the contrast area after forecast conversion. CONSTITUTION:After a mixed picture between a character/line drawing and a contrast picture fed to an input terminal 1 is set to a register 2, the picture is fed to a shift register 3, an exclusive OR circuit 4 and a multiplexer 7. A means comprising a ROM 10, a register 11 and a line counter 10 discriminates whether an area is a character/line picture area or a contrast area. When the area is discriminated as the character/line picture area, the input picture data is fed to an MH coder 8 via the multiplexer 7 to apply MH coding, and when the area is discriminated as the contrast area, the input picture data is subjected to forecast conversion, the result is fed to the MH coder 8 via the multiplexer 7 as a smoothed forecast error signal (e) to attain MH coding.
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