Image analysis – Pattern recognition – On-line recognition of handwritten characters
Patent
1995-06-07
1997-05-06
Razavi, Michael T.
Image analysis
Pattern recognition
On-line recognition of handwritten characters
382229, 364735, 395759, G06K 972
Patent
active
056279140
ABSTRACT:
A method for processing equations in a graphical computer system characterized by the steps of: receiving at least one unit comprising an equation which was derived from a graphical user input device; parsing the units into a parsed tree utilizing a constrained attribute grammar; and deriving a result of the equation utilizing the parsed tree. Preferably, the graphical user input device is a table or the screen of a pen-based computer system, where stroke units derived from strokes made by a stylus on the screen are passed to at least one recognition domain. The process preferably also includes the steps of: receiving at least one stroke unit comprising an edit to an equation on the screen; determining whether the edit changes the structure of the parsed tree of the equation; and editing the parsed tree if the edit does not change the structure of the parsed tree. A system for processing equations is characterized by: a digital processor; a screen assembly coupled to the digital processor for displaying images in response to signals provided by the digital processor and for transmitting signals to the digital processor in response to stroke made on the screen assembly with a stylus; all equation recognizer responsive to the stroke signals and operative to detect valid equations formed on the screen; an equation solver operative to produce a result for valid equations; and a mechanism for displaying the result on the screen assembly proximate to the equation.
REFERENCES:
patent: 4688195 (1987-08-01), Thompson et al.
patent: 4845652 (1989-07-01), Bunsen
patent: 5083268 (1992-01-01), Hemphill et al.
patent: 5157737 (1992-10-01), Sklarew
patent: 5189633 (1993-02-01), Bonadio
patent: 5251292 (1993-10-01), Martel, Jr. et al.
Anderson, Robert H., "Syntax-Directed Recognition of Hand-Printed Two-Dimensional Mathematics," Interactive Systems for Experimental Applied Mathematics, New York, Academic Press, 1981, pp. 436-459.
W. Tsai et al., "Attributed Grammar-A Tool for Combining Syntatic and Statistical Approaches to Pattern Recognition," IEEE Transactions on Systems, Man, and Cybernetics, vol. SMC-10, No. 12, Dec. 1980, pp. 873-885.
O'Connor, Rory J., "Apple Banking on Newton's Brain," San Jose Mercury News, Apr. 22, 1992.
Weiman, Liza et al., "A Step Toward the Future, " Macworld, Aug. 1992, pp. 129-131.
Soviero, Marcelle M., "Your World According to Newton," Popular Science, Sep. 1992, pp. 45-49.
Abatemarco, Fred, "From the Editor," Popular Science, Sep. 1992, p. 4.
"Macintosh User's Guide," Apple computer, Inc. 1991, pp. 47-50.
Blackwell, F. W. et al., "An On-Line Symbolic Mathematics Systems Using Hand-Printed Two-Dimensional Notation," Rand Corporation, Jan. 1970, pp. 1-18.
Helm, Richard et al., "Building Visual Language Parsers," Reaching Through Technology, ACM Press, CHI'91 Conference Proceedings.
Belaid, Abdelwaheb et al., "A Syntactic Approach for Handwritten Mathematical Formula Recognition," IEEE Trans. on Pattern Analysis & Machine Intelligence, Jan. 1984, vol. PAMI-6, No. 1, pp.105-111.
Truve, S. "Image Interpretation Using Multi-Relational Grammars," IEEE Comput. Soc. Press, 1990, pp. 146-155.
Naini, Majid M. "A New Efficient Incremental Evaluator for Attribute Grammars Allowing Conditional Semantic Equations," IEEE, 1988, pp. 386-390.
Williams, Thomas G., "On-Line Parsing of Hand-Printed Mathematical Expressions: Final Report for Phase II," Clearinghouse, Dec. 27, 1968, pp. 1-19.
El-Sheikh, "Recognition of Handwritten Arabic Mathematical Formulas," IEEE, Mar. 1990, pp. 344-351.
Avitzur, Ron, "Your Own Handprinting Recognition Engine: Algorithms for Putting Pen to Pad", Dr. Dobb's Journal, Apr. 1992, vol. 17, No. 4, p. 32(5).
Apple Computer Inc.
Chang Jon
Razavi Michael T.
LandOfFree
Method and apparatus for processing graphically input equations 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 processing graphically input equations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for processing graphically input equations will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2138895