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. 23, 2003
Filed:
Nov. 02, 2001
Arie Berman, Chatsworth, CA (US);
Paul Vlahos, Tarzana, CA (US);
Arpag Dadourian, Northridge, CA (US);
iMatte, Inc., Chatsworth, CA (US);
Abstract
Changes in a current image frame from variations in room light level, and automatic camera adjustments, are determined and incorporated into a clear (reference) frame, thereby resulting in a zero difference in the background region when the clear frame and a current frame are subtracted. Any deviation from zero defines the beginning edge of a transition from background to subject. The location of the outer edge of a transition area is further refined by subtracting derivatives of the RGB signals in each frame, and by the use of a fourth color channel when available. The difference of derivitives (d -d ) identifies the subject to background transition area, whose edges define the inner and outer boundary lines. Shadow areas on the backing are retained and may be transferred to the inserted background scene. Small areas on the backing having the same color and luminance as the subject are prevented from printing through the subject by a second “derivative” alpha channel for the small areas.