04675724 is referenced by 31 patents and cites 23 patents.

In a time base correction system, a composite color television analog signal derived from a prerecorded tape is converted by an analog-to-digital (A/D) converter to a digital signal having horizontal sync and color burst signal components. The digitized sync and burst signals are processed on a line-by-line basis to provide an error signal between input video and a sampling clock in the form of a binary control word. The error signal is applied to a digital frequency synthesizer which generates a clock at the subcarrier frequency to achieve precise adjustment of frequency and phase of the A/D sampling clock with respect to the video signal. An analog phase locked loop operating at four times the subcarrier frequency feeds back a 4.times. subcarrier sampling clock to the analog-to-digital converter with adjustable frequency and phase.

Title
Video signal phase and frequency correction using a digital off-tape clock generator
Application Number
6/781293
Publication Number
4675724
Application Date
September 27, 1985
Publication Date
June 23, 1987
Inventor
Steven D Wagner
San Jose
CA, US
Agent
Joel D Talcott
George B Almeida
Nathan N Kallman
Assignee
Ampex Corporation
CA, US
IPC
H04N 5/95
H04N 9/89
H04N 9/455
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