发明名称 |
METHOD AND APPARATUS FOR ADAPTIVELY THRESHOLDING GRAYSCALE IMAGE DATA |
摘要 |
A method of generating a remapping function for use in converting near-photographic document image pixel gray level data lying in a first range of gray level values to higher contrast, background-suppressed pixel gray level data lying in a second more limited gray level range. Global document information, such as a histogram of all the document's original pixels, is used to generate at least one threshold gray level value and to determine the shape of the remapping function on either side of the threshold. Preferably, the remapping function is implemented by a look-up table addressed in accordance with the original pixel data. |
申请公布号 |
WO9220183(A3) |
申请公布日期 |
1993.01.07 |
申请号 |
WO1992US03480 |
申请日期 |
1992.04.24 |
申请人 |
UNISYS CORPORATION |
发明人 |
KIDD, ROBERT, CHARLES;KLEIN, ROBERT, DENNIS |
分类号 |
G09G5/10;G06K9/38;G06T5/00;G09G5/42;H04N1/403;H04N1/407;H04N1/41 |
主分类号 |
G09G5/10 |
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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