05392365 is referenced by 137 patents and cites 12 patents.

Apparatus for detecting edges of black text in an original image. An edge detector which low pass filters the image signal to blur and widen any edges in the original image, and then high pass filters the low pass filtered signal to produce a first output signal which represents the blurred edges in the original image. The non-edge blurred signal is high pass filtered to produce a second output signal which represents the non-blurred edges in the original image. The first and second output signals are combined to create a first edge control signal that encompasses any edges in the original image. Halftone areas of the original image are identified by detecting dots in the original image, a second edge control signal that excludes areas in the original image identified as containing dots is created. Color pixels in the original image are detected, and a neutral color signal that represents the non-color portions of the original image is created. The first edge control signal, the second edge control signal, and the neutral color signal are combined to create a black text edge control signal that encompasses edges in the original image not in an area that contains dots.

Title
Apparatus for detecting text edges in digital image processing
Application Number
7/812666
Publication Number
5392365
Application Date
December 23, 1991
Publication Date
February 21, 1995
Inventor
James J Steinkirchner
Brockport
NY, US
Agent
Norman Rushefsky
Assignee
Eastman Kodak Company
NY, US
IPC
G06K 9/48
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