PURPOSE: To reproduce a picture mixed with a photographic picture and characters in good way, by sectioning a part having the priority of reproduction of high gradation and a part having the priority of high resolution in block unit.

CONSTITUTION: When switches 17 and 18 are selected at the position as shown in Figure, picture information is stored in a picture memory 9. The switches 17 and 18 are changed over and the content of the memory 9 is sequentially processed while the picture information is written in a memory 10. As to the content of the memory 9, the picture information corresponding to one block is transferred to a block memory 11, and a difference between the maximum and minimum density level out of picture elements in the block is compared with a predetermined value m at a picture quality discrimination circuit 13. Whether binarization with an organic dither or that with a prescribed threshold value is discriminated. A switching circuit 16 can select a threshold memory 14 of an organic dither or a prescribed threshold value memory 15. A binary circuit 12 compares the output of the memory 11 with that of the circuit 16 to output a binary signal.