发明名称 |
Optical scanner threshold setting method and sheet |
摘要 |
A method for the optimization of optical scanners by automatically determining image processing threshold values using a novel threshold calibration sheet. The calibration sheet image has lines at a forty-five degree angle to the path of the document through the scanner and has a predetermined image dot count. One embodiment comprises the steps of repetitively scanning the sheet until scanner threshold values which satisfy predetermined relationships with said dot count are determined. Another embodiment comprises the steps of a single calibration scan with multiple processing of the gray scale scan data on a host computer. By using this method, two or more scanner cameras can work together on processing document images and consistently give uniform results, independent of their individual technical operating or performance differences.
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申请公布号 |
US5194966(A) |
申请公布日期 |
1993.03.16 |
申请号 |
US19900616134 |
申请日期 |
1990.11.20 |
申请人 |
EDUCATIONAL TESTING SERVICE |
发明人 |
QUARDT, DENNIS;CHANG, KER-MING |
分类号 |
H04N1/00;H04N1/403 |
主分类号 |
H04N1/00 |
代理机构 |
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代理人 |
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地址 |
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