Image analysis – Pattern recognition – On-line recognition of handwritten characters
Patent
1993-09-30
1996-12-10
Couso, Jose L.
Image analysis
Pattern recognition
On-line recognition of handwritten characters
382173, 395326, G06K 900
Patent
active
055839460
ABSTRACT:
A method and apparatus for recognizing a gesture input on a display screen of a computer system. A method of recognizing an ellipse gesture comprises the steps of receiving a stroke input by a user onto a computer screen, smoothing the stroke by reducing the number of points that represent the stroke, determining whether the smoothed stroke includes at least a predetermined minimum number of points, and, if so, calculating angles between adjacent segments of the smoothed stroke and calculating derivatives of the angles. It is determined if the stroke substantially represents an ellipse by utilizing the angles and the derivatives of the angles. The method preferably includes selecting an ink object on the screen if the ink object is substantially overlapped by the smoothed stroke. A different method of implementing fuzzy recognition includes smoothing the stroke, normalizing the smoothed stroke, determining whether the normalized stroke matches one of a plurality of gesture prototypes, and, if so, selecting the gesture associated with the best matched gesture prototype as the appropriate interpretation of the stroke. The step of normalizing the stroke preferably includes storing normalized coordinates in at least one prototype buffer. The normalized stroke is matched to one or more of a plurality of gesture prototypes by utilizing a correlation score that is calculated for each prototype. The gesture prototypes preferably include standard gestures, such as bracket gestures and pigtail gestures, well as gestures input by a user that represent one of said standard gestures. An alternative embodiment of both methods includes a step of determining whether the stroke is part of a multiple stroke gesture, and, if so, adding the stroke to stroke portions previously input by the user.
REFERENCES:
patent: 4365235 (1982-12-01), Greanias et al.
patent: 4680804 (1987-07-01), Kuzunuki et al.
patent: 4739317 (1988-04-01), Berry et al.
patent: 4812832 (1989-03-01), Oishi et al.
patent: 4821030 (1989-04-01), Batson et al.
patent: 4992630 (1991-02-01), Mletzko
patent: 5034989 (1991-07-01), Loh
patent: 5038382 (1991-08-01), Lipscomb
patent: 5063600 (1991-11-01), Norwood
patent: 5121442 (1992-06-01), Togawa et al.
patent: 5157737 (1992-10-01), Sklarew
patent: 5218645 (1993-06-01), Bacus
patent: 5220649 (1993-06-01), Forcier
Valdes, Ray, "DDJ Handprinting Recognition Context Wrap-up", Dr. Dobb's Journal, Jan. 1993.
"Using Penpoint" Developer Release Operators Manual for PenPoint Operating System, by Go Corporation, Foster City, California.
Apple Computer Inc.
Couso Jose L.
LandOfFree
Method and apparatus for recognizing gestures on a computer syst 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 recognizing gestures on a computer syst, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for recognizing gestures on a computer syst will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-430674