| 摘要 |
PURPOSE:To obtain an accurate decision result even when a registered seal impression and a seal impression to be collated are different in density, by adjusting the threshold level of the seal impression to be collated according to its density. CONSTITUTION:When the registered seal impression stored in an original register file part 15 is collated with the seal impression to be collated from a picture input means, a binary coding means 16 generates a binary-coded signal on the basis of the registered seal impression. Then, a histogram generating means 12 generates a multilevel histogram from data on the seal impression to be collated and a binary-coded signal based upon the histogram is generated by a binary- coding means 18. The binary outputs of the binary coding means 16 and 18 are compred with each other and according to its output, the binary coding level of the binary coding means 18 is controlled. |
