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:
Aug. 04, 2009
Filed:
Aug. 27, 2007
Jian Wang, Beijing, CN;
Yingnong Dang, Beijing, CN;
Qiang Wang, Beijing, CN;
Liyong Chen, Beijing, CN;
Xiaoxu MA, Cambridge, MA (US);
Jian Wang, Beijing, CN;
Yingnong Dang, Beijing, CN;
Qiang Wang, Beijing, CN;
Liyong Chen, Beijing, CN;
Xiaoxu Ma, Cambridge, MA (US);
Microsoft Corporation, Redmond, WA (US);
Abstract
Systems and methods that determine a path of a pen tip as the pen tip is moved across a document are described. The document is watermarked with a maze pattern from which encoded position information is determined. A sequence of images is captured by a camera that is located in a pen. The path of the pen tip is determined by decoding the associated maze pattern and by matching the captured images with document images. If the position coordinates of any frame that is associated with a stroke cannot be determined from m-array decoding, the frames are transformed and then matched with an area of a document image. Once the position coordinates of at least one frame is determined, the position coordinates of other frames are determined by matching the frames in a neighboring area.