发明名称 |
Method and apparatus for converting halftone images |
摘要 |
The edge feature value of a M-valued original image is detected and converted to an N-valued image (where M>N) using an error diffusion method while suppressing the quantization error in edge areas of the image by edge area enhancement. The N-valued image data is scanned with a edge feature value detection filter to detect feature quantities and is scanned by plural spatial filters with different smoothing characteristics to normalize the output value of each spatial filter to a specific value. The normalized outputs of the spatial filters are weighted with a weighting coefficient based on the edge feature value to generate the interpolated image data, and the resulting image is normalized to L-valued image data (where N<L). The mixing ratio and image quality are also controlled by manipulating the edge feature value and weighting coefficients.
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申请公布号 |
US5454052(A) |
申请公布日期 |
1995.09.26 |
申请号 |
US19930044827 |
申请日期 |
1993.04.08 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
KOJIMA, AKIO |
分类号 |
H04N1/409;G06T5/00;G06T5/20;H04N1/405;H04N1/407;H04N1/41;(IPC1-7):G06K9/00 |
主分类号 |
H04N1/409 |
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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