04792979 is referenced by 39 patents and cites 6 patents.

A standard gradation correction curve independent of characteristics of an original image is prepared in advance. An accumulated density historgram curve of the original is obtained from image data of the original. A first gradation correction curve is obtained by modifying the standard gradation correction curve, while a second gradation correction curve is obtained by modifying the accumulated density histogram curve. A third gradation correction curve is obtained by linear combination of the first and second gradation conversion curves to perform gradation correction of the image data on the basis of the third gradation correction curve.

Title
Method of and apparatus for correcting gradation of image represented by image data
Application Number
7/82334
Publication Number
4792979
Application Date
August 6, 1987
Publication Date
December 20, 1988
Inventor
Yasuo Kurusu
Kyoto
JP
Akihiro Nomura
Osaka
JP
Agent
Lowe Price LeBlanc Becker & Shup
Assignee
Dainippon Screen Mfg
JP
IPC
G06K 9/36
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