| 摘要 |
PURPOSE:To discriminate a half tone region in real time, by carrying out a dither process and a simple binary coding process individually for a multivalue digital picture, obtaining the mean value of the preprocess density for the picture elements which are decided black and white through the above-mentioned processes and using these mean values. CONSTITUTION:Input picture data is supplied to a shift register 101 at the highest stage of an input buffer 100, a simple binary coding circuit 105, a dither circuit 106 plus multiplexers 107 and 108, respectively. The circuit 105 compares the level of density of the picture element to be supplied with the set threshold value. The circuit 106 compares the above-mentioned level of concentration with the corresponding element within a dither matrix. Then the mean value of the preprocess density is obtained for the picture elements which are decided black and white each through the dither and simple binary coding processes. Based on these values, a deciding circuit 121 decides whether or not each mesh region is equal to a half tone region. |
