发明名称 |
Digital halftoning apparatus and method |
摘要 |
A raster device such as a digital printer or the like which sequentially compares input image data with each element in a threshold matrix to convert the input image data into binary or multi-level pixel data. For providing both a higher resolution and a larger number of halftone levels for an output image at a low cost, an input image is decomposed into four color planes as CMYK data, and data on each color plane is compared with a dither matrix in a binarization circuit to be converted to binary data. The dither matrix generates a dither pattern composed of eight clusters having substantially the same shape as a kernel cluster capable of expressing 15 or more halftone levels. In this way, a smooth gradation having 120 or more halftone levels is realized by repetitively applying a small pattern having approximately 15 halftone levels.
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申请公布号 |
US5867607(A) |
申请公布日期 |
1999.02.02 |
申请号 |
US19960617032 |
申请日期 |
1996.03.18 |
申请人 |
HITACHI, LTD. |
发明人 |
SHIBUYA, TAKESHI;SATOU, TATSUNARI;SEINO, TAISAKU |
分类号 |
B41J2/52;G06T5/00;H04N1/405;H04N1/52;(IPC1-7):G06K9/38;H04N1/40 |
主分类号 |
B41J2/52 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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