Facsimile and static presentation processing – Facsimile – Specific signal processing circuitry
Patent
1984-09-20
1986-09-09
Groody, James J.
Facsimile and static presentation processing
Facsimile
Specific signal processing circuitry
358903, 375106, 340814, H04N 504
Patent
active
046112286
ABSTRACT:
Disclosed is a synchronizer for establishing synchronism between horizontal and vertical sync pulses of a non-interlaced video signal and those of an interlaced video signal, the number of non-interlaced scan lines being smaller by 2n-1 than the interlaced scan lines, where n is an integer equal to or greater than unity. Two variable frequency clocks are generated, one having a higher frequency variable as a function of a phase difference between the horizontal sync pulses of the two video signals and the other having one half the higher frequency. A first period is defined which runs from a non-interlaced horizontal sync of first occurrence in a given field to a horizontal sync of (n-1)th occurrence in the given field and a second period is defined that runs from the non-interlaced horizontal sync of first occurrence in a subsequent field to a horizontal sync of n-th occurrence in the subsequent field. The higher frequency clock is normally used to generate the non-interlaced horizontal and vertical sync and the lower frequency clock is used instead when vertical sync pulses of the two video signals are mismatched in phase and during the first and second periods to compensate for the difference in scan line number.
REFERENCES:
patent: 2752424 (1956-06-01), Pugsley
patent: 3112364 (1963-11-01), Myles
patent: 3311702 (1967-03-01), Legler
patent: 3567861 (1971-03-01), Webb et al.
patent: 3628159 (1971-12-01), Ellis
patent: 4134131 (1979-01-01), Hopkins, Jr.
patent: 4253116 (1981-02-01), Rodgers, III
patent: 4346407 (1982-08-01), Baer et al.
patent: 4520393 (1985-05-01), Zwijsen et al.
Machida Toyotaka
Matsumoto Hiroaki
Nakamura Akira
Shinyagaito Tatsuya
Ueguri Shigeharu
Groody James J.
Parker Michael D.
Victor Company of Japan Ltd.
LandOfFree
Scan line synchronizer does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Scan line synchronizer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Scan line synchronizer will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1017860