Television – Synchronization – Automatic phase or frequency control
Patent
1995-12-22
1998-07-28
Grant, Chris
Television
Synchronization
Automatic phase or frequency control
348500, H04N 512
Patent
active
057868689
ABSTRACT:
An automatic step generator that monitors and corrects the sampling rate in a video signal. The invention isolates a sampling window in the prevailing sampling rate, the window advantageously being 144 lines for NTSC, or 231 lines for PAL, or some other preselected window wherein the sample count therein at an ideal sampling rate approximates an integer power of 2. The invention then calculates the numeric difference between that ideal sample count in the window and the preselected integer power of 2. The actual sample count in the window is then determined, and is adjusted by the numeric difference between the ideal count and the integer power of 2. Variations in this adjusted actual sample count and the integer power of 2 will thus represent variations between the actual sampling rate and the ideal sampling rate. A step value to correct the actual sampling rate to achieve the ideal rate may then be derived by dividing the adjusted actual sample count by the integer power of 2. In binary, this division is simply a shift right in bit significance. The step value may thus be derived directly and immediately from the adjusted sample count.
REFERENCES:
patent: 4463371 (1984-07-01), Lewis, Jr.
patent: 4612568 (1986-09-01), den Hollander et al.
patent: 4635097 (1987-01-01), Tatami
patent: 4694326 (1987-09-01), Demmer
patent: 4736238 (1988-04-01), Moriyama et al.
patent: 4797730 (1989-01-01), Smith
patent: 4905085 (1990-02-01), Faulhaber
patent: 4941035 (1990-07-01), Judge
patent: 4970581 (1990-11-01), O'Gwynn
patent: 4975767 (1990-12-01), Sorenson
patent: 5043799 (1991-08-01), Kohiyama et al.
patent: 5243412 (1993-09-01), Goukura et al.
patent: 5325093 (1994-06-01), Takamori
Cirrus Logic Inc.
Grant Chris
Shaw Steven A.
Tannenbaum David H.
LandOfFree
Automatic step generator for self-correction of sampling does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Automatic step generator for self-correction of sampling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic step generator for self-correction of sampling will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-26876