US4612573A
Expired / Lapsed
US
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Method for clock rate conversion
Assignee: Siemens AG
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Filing: 1984-09-14
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Granted: 1986-09-16
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Expires: 2004-09-14
Abstract
Abstract A method for clock rate conversion of digitized television signals for the acquisition of a television signal having a prescribed processing clock rate is provided wherein the digitized television signal is band-limited, a clock rate conversion being subsequently undertaken. The television signal having a second clock rate is written into a memory 6 and is, in turn, read with the prescribed processing clock rate, whereby an unaltering plurality of data words corresponding to picture points is not output in every television line.
Inventors
- 👤 Hans-Joachim Grallert
- 👤 Alexander Starck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:00
CPC Classifications
H; H04; H04N; H04N11/00; H04N11/04; H04N7/00; H04N7/01; H04N7/0102
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
150 words
A clock rate conversion method for first digitized television signals of television lines sampled at a first clock rate into second television signals having a predetermined processing clock rate, comprising the steps of: generating clock signals having a first clock rate (f T1 ), a second clock rate (f T2 ) and, as the predetermined processing clock rate, a third clock rate (f T3 ), where the second clock rate is related to the first clock rate by a rational number conversion factor (C) and is close to the third clock rate; sampling the first digitized television signals at the first clock rate (f T1 ) to obtain data words; converting the data words to the second clock rate (f T2 ) and storing the same; and reading a plurality of data words (K±m) of K data words of each television line at the third clock rate (f T3 ).
Claim 2
Dependent Claim
150 words
A clock rate conversion method for first digitized television signals of television lines sampled at a first clock rate into second television signals having a predetermined processing clock rate, comprising the steps of: generating clock signals having a first clock rate (f T1 ), a second clock rate (f T2 ) and, as the predetermined processing clock rate, a third clock rate (f T3 ), where the second clock rate is related to the first clock rate by a rational number conversion factor (C) and is close to the third clock rate; sampling the first digitized television signals at the first clock rate (f T1 ) to obtain data words; converting the data words to the second clock rate (f T2 ) and storing the same; and reading a plurality of data words (K±m) of K data words of each television line at the third clock rate (f T3 ).
Claim 3
Dependent Claim
22 words
The method of claim 1, wherein the step of storing is further defined as: storing the data words on a first-in/first-out basis.
Claim 4
Dependent Claim
43 words
The method of claim 1, wherein the step of generating clock signals is further defined as: generating the first clock rate (f T1 ) at 13.5 MHz; and generating the second clock rate at 10.125 MHz with a conversion factor (C) of 3/4.
Claim 5
Dependent Claim
50 words
The method of claim 1, wherein the step of storing and reading are further defined as: storing 526 data words for each television line on a first-in/first-out basis; and reading all of the data words for each line except the first three data words and the last three data words.
Claim 6
Dependent Claim
31 words
The method of claim 1, wherein the step of reading is further defined as: reading more data words than stored for each television line as a black or gray luminance value.
Claim 7
Dependent Claim
23 words
The method of claim 1, and further comprising the step of: filtering the sampled first digitized television signals with a digital low-pass filter.
Claim 8
Dependent Claim
26 words
The method of claim 1, wherein the step of generating clock signals is further defined as: generating the clock signals with at least one phase-locked loop.
Claim 9
Dependent Claim
27 words
The method of claim 1, and further comprising the step of: selecting the conversion factor (C) to have the lowest possible numerator and the lowest possible denominator.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-15 | 1990-03-17 | 1990-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-15 | 1994-03-17 | 1994-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-15 | 1998-03-17 | 1998-09-16 | $7700.00 | Window Closed / Lapsed |