| 摘要 |
PURPOSE:To obtain excellent picture information, by reading picture information to be transmitted after the picture value is binary quantitized with a picture element density which is higher than that of the picture information to be transmitted, and by selecting picture information to be transmitted actually based on the information. CONSTITUTION:Picture information data obtained by reading an original picture after the original picture is binary quantitized with a double density, are stored in a memory buffer 10 of scanning lines for double density. The data are read out two bits by two bits by a shift register 11 as double density data (b), and the output (b') of the register 11 is added to an ROM table 12. To the other input of the table 12, feedback information (c') of 1-bit transmitting picture information (c) previously determined by the table 12 is added from a latch circuit 13. The table 12 has a table corresponding to a determined function and reads out relevant 1-bit transmitting picture information from the table based on the inputs (b') and (c'). The above mentioned operation is repeated and picture information to be transmitted is determined from the double density data. Moreover, yi=F(yi-1, X2i-1, X2i) is used as the determined function. |
