07158686 is referenced by 43 patents and cites 16 patents.

A method of producing a tone scale function which operates on a source digital image to improve tonal characteristics, includes receiving a source digital image including a plurality of pixels; and producing a tone scale function having a highlight tone scale segment and a shadow tone scale segment defined relative to a reference point on the tone scale function, and that is adapted to operate on the source digital image, wherein the highlight tone scale segment is defined by a different mathematical function than the shadow tone scale segment; at least one of the highlight tone scale or shadow tone scale segments have at least one inflection point; the highlight tone scale segment is defined for points that are equal to or greater than the reference point; and the shadow tone scale segment is defined for points that are equal to or less than the reference point.

Title
Enhancing the tonal characteristics of digital images using inflection points in a tone scale function
Application Number
10/246856
Publication Number
7158686 (B2)
Application Date
September 19, 2002
Publication Date
January 2, 2007
Inventor
Edward B Gindele
Rochester
NY, US
Agent
Raymond L Owens
Assignee
Eastman Kodak Company
NY, US
IPC
G06K 9/00
G06K 9/38
G06K 9/40
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