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:
Jun. 16, 1987
Filed:
Mar. 23, 1984
Andrew B Lippman, Salem, MA (US);
Victor M Bove, Jr, Cambridge, MA (US);
Jerome B Wiesner, Watertown, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
A technique for handling video signals so as to permit such signals to be satisfactorily displayed on video display devices, such as TV receivers or monitors, but to prevent such signals from being satisfactorily recorded by video recording devices. In a particular embodiment thereof the video frame time base is altered in a selected manner, as by lengthening or shortening the time bases of successive video frames, or successive groups of video frames. The alterations thereof can be in discrete steps and be performed cyclically so that during each overall cyclical time period the cumulative error is zero.