发明名称 |
Image processing method for graphics images |
摘要 |
Graphics images are generally considered to be those images comprised of text and/or line drawings. Data compression of graphics images is desired whenever a fast image transmission speed is desired in a limited band width channel. It is also used for storage of a large number of images in a limited capacity storage system. The method and apparatus described herein improves data compression, resolution and coding efficiency by eliminating transitions between gray levels at edges in an image, converting all gray levels to a common value to achieve a 3 level representation of a graphics image, and reversibly converting the 3 level representation to a bilevel double resolution representation by increasing the data sampling rate and therefore allowing the use of two level data compression techniques. A high resolution display or printed output may be obtained from the bilevel multiresolution representation.
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申请公布号 |
US4558370(A) |
申请公布日期 |
1985.12.10 |
申请号 |
US19830553216 |
申请日期 |
1983.11.21 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
MITCHELL, JOAN L.;PENNEBAKER, WILLIAM B. |
分类号 |
H04N1/403;G06T1/20;G06T3/40;G06T5/00;H04N1/40;H04N1/41;(IPC1-7):H04N1/40;G06K9/36;G09G1/14;G09G3/00 |
主分类号 |
H04N1/403 |
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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