| 摘要 |
PURPOSE:To separate easily and surely an intermediate tone picture and a binary picture image by deciding that data fall into a binary character region when the result obtained by subtracting the read data of an input picture from its binary coded data is a prescribed value or smaller, and when the result is a prescribed value or greater, the data fall into an intermediate tone picture region. CONSTITUTION:A picture data read by a reading device 3 is stored in a memory 4. A maximum value and a minimum value of the picture data in the memory 4 are detected by a maximum value and minimum value detecting circuit 5 and inputted to a fixed binary-coding circuit 6. An intermediate value between the maximum value and the minimum value is set in the circuit 6 as a threshold value, and the picture data is binary-coded and stored in a memory 7. The contents of the memory 7 are subtracted from the contents of the memory 4 at a subtraction circuit 8, a discriminating circuit 9 discriminates whether or not the subtracted value is nearly 0, and inputs the result to a dot pattern generating circuit 10. The circuit 10 discriminates that the input picture is a data for the binary character image region 2 when the result of subtraction is nearly 0 and discriminates it as a data in the intermediate tone picture region 1 when the result of subtraction is other than nearly 0, thereby using a dot matrix pattern depending on the case and prints the picture on paper. |
