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:
Jan. 06, 1987
Filed:
Feb. 04, 1985
Warren H Nicholson, Plainsboro, NJ (US);
Walter E Sepp, Plainsboro Township, Middlesex County, NJ (US);
RCA Corporation, Princeton, NJ (US);
Abstract
Circuitry for detecting nonstandard video signals is disclosed. This circuitry is used in a sampled data video signal processing system to control signal processing steps which utilize a frame store memory. The detecting circuitry includes a programmable counter which generates a standard horizontal pulse signal having a 70 ns pulse width by counting down a sampling clock signal that has a frequency proportional to the color subcarrier frequency of the video signals. The circuitry generates another horizontal pulse signal having a pulse width of less than 140 ns from the horizontal sync pulses of the input video signals. These pulse signals are compared in a coincidence detector which produces a signal that is in a first state when the pulses of the two signals overlap at least once in every twenty-five horizontal line times and in a second state otherwise. This coincidence signal and the field rate vertical synchronizing signal from the input video signal are used to generate the control signal for the frame store memory. This control signal is in a first state when the coincidence signal has been in its first state for at least one frame time and that changes to a second state when the coincidence signal changes to its second state.