Image analysis – Image transformation or preprocessing – Measuring image properties
Patent
1993-12-20
1998-10-06
Couso, Yon J.
Image analysis
Image transformation or preprocessing
Measuring image properties
382296, G06K 932
Patent
active
058189769
ABSTRACT:
The present invention relates in general to optical scanning and image processing, and relates more particularly to a document imaging system which detects skew and/or detects size/shape of a document image. Preferred embodiments utilize a background with optical characteristics which contrast with those of the scanned document. In one embodiment, a document imaging system generates scanning signals in response to optical characteristics of a medium such as a sheet of paper, detects transitions in the scanning signal which define points along one or more edges of the medium, establishes a skew angle between the detected edges and a reference orientation, and compensates for skew by modifying the scanning signals as required such that the resultant skew angle is substantially equal to zero. In another embodiment, a document imaging system detects one or more edges of a document, defines a polygon having sides substantially congruent with the detected edges, and establishes the size of the document in response to the polygon.
REFERENCES:
patent: 4620288 (1986-10-01), Welmers
patent: 4802229 (1989-01-01), Yamada
patent: 4823395 (1989-04-01), Chikauchi
patent: 4926490 (1990-05-01), Mano
patent: 4953230 (1990-08-01), Kurose
patent: 4980781 (1990-12-01), Yamamoto et al.
patent: 5027227 (1991-06-01), Kita
patent: 5086486 (1992-02-01), Yamada
patent: 5093653 (1992-03-01), Ikehira
patent: 5191438 (1993-03-01), Katsurada et al.
patent: 5276530 (1994-01-01), Siegel
patent: 5373371 (1994-12-01), Masui
patent: 5455690 (1995-10-01), Ishikawa
A.W. Paeth, "A Fast Algorithm for General Raster Rotation," Graphics Gems, A.S. Glassner, ed., 1990, pp. 179-195.
"Kofax Unveils KF-9275 Advaced Document Processor", News Release, Chicago, IL, Apr. 6, 1993.
"Scanning Time Saved by Ideal's Cadimage/Scan Breakthrough", News Release, Rockville, MD. Jun. 2, 1992.
"Ideal Releases New Scanning Software", Electronic Imaging Report, v.2 No. 12 Jun. 12, 1992.
"Calcomp Introduces Large-Format, Multiplatform Scanplus 17 Four Models Meet Wide Range of Users' Performance Needs", News Release, Scottsdale, AZ, Mar. 26, 1993.
"Automatic Extraction of Original Features in a Copy Machine," Research Disclosure No. 328, Emsworth, GB, Aug. 1991, p. 594.
Cotte Pierre-Alain
Papuc Sorin Vasile
Pasco Richard Clark
Couso Yon J.
Gallagher Thomas A.
Lathrop David N.
Visioneer, Inc.
LandOfFree
Method and apparatus for document skew and size/shape detection does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for document skew and size/shape detection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for document skew and size/shape detection will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-87998