| 摘要 |
PURPOSE:To surely detect a code with a relatively simple constitution by subjecting the code, which is obtained by digitizing an input picture and is printed, to binarization processing after low-pass filter processing. CONSTITUTION:The primary picture converted to a digital signal by an A/D converter 42 is stored in a temporary memory 51. Contents of the primary memory 51 are stored in a secondary memory 53 through a picture improving space filter 52. Shading information is extracted by a shading generator 54 and is stored in a shading memory 52. Contents of the secondary memory 53 and the shading memory 55 are inputted to a shading corrector 56 and are converted to a binary picture by a binarizer 57, whose discrimination level is designated by a threshold register 58, after elimination of shading and are stored in a binary picture memory 59. The space filter 52 reduces a high-band noise or emphasizes a high-band signal by two-dimensional convolutional operation of the picture. |
