The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 31, 1996
Filed:
Mar. 16, 1995
Arnaud P Gourdol, Cupertino, CA (US);
Apple Computer, Inc., Cupertino, CA (US);
Abstract
A method and apparatus for recognizing an ellipse-type gesture input on a display screen of a computer system. A stroke is input by a user onto a computer screen, and the stroke is smoothed by reducing the number of points that represent the stroke. It is determined whether the smoothed stroke includes at least a predetermined minimum number of points, and, if so, angles between adjacent segments of the smoothed stroke and derivatives of the angles are calculated. It is determined if the stroke substantially represents an ellipse by checking if the stroke curves in one direction or more than one direction utilizing the angles and the derivatives of the angles. In addition, the stroke represents an ellipse if the end points are within a predetermined distance of each other, and if a sum of the derivatives of the angles is within a predetermined range of values. The method preferably includes selecting an object on the screen if the object is substantially overlapped by the smoothed stroke. An alternative embodiment includes 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.