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US3947638A
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Pitch analyzer using log-tapped delay line
Assignee: United States Department of the Army
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Filing: 1975-02-18
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Granted: 1976-03-30
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Expires: 1995-02-18
Abstract
Abstract A pitch analyzer is described which extracts, on a real-time or pipeline is, the pitch information from a speech signal. The analyzer converts the speech signal to a digital signal, shifts it into a delay line tapped at logarithmic intervals and constructs a measure of merit for each of many possible pitch periods. These measures are periodically transferred to a processor which combines them in a prescribed manner with previous information to select the one most-likely current value of pitch. Provision is also made, when the application warrants it, to select the best pitch value, with a delay of several frames, based on current information.
Inventors
- 👤 William A. Blankinship
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:10
CPC Classifications
G; G10; G10L; G10L25/00; G10L25/90
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
61 words
A pitch analyzer, comprising: means for digitizing an analog speech signal; a delay line into which said digitized signal may be sequentially inserted; means for periodically extracting the contents of selected stages of the delay line, the selected stages being spaced at substantially logarithmic intervals; and means for periodically testing said extracted contents to determine an optimum choice of pitch period.
Claim 2
Dependent Claim
61 words
A pitch analyzer, comprising: means for digitizing an analog speech signal; a delay line into which said digitized signal may be sequentially inserted; means for periodically extracting the contents of selected stages of the delay line, the selected stages being spaced at substantially logarithmic intervals; and means for periodically testing said extracted contents to determine an optimum choice of pitch period.
Claim 3
Dependent Claim
30 words
The pitch analyzer of claim 1, wherein the length of said delay line is sufficient to store a sample of speech having greater length than the greatest anticipated pitch period.
Claim 4
Dependent Claim
19 words
The pitch analyzer of claim 2, wherein each column of the delay line stores one sample of speech information.
Claim 5
Dependent Claim
31 words
The pitch analyzer of claim 3, wherein the contents of the delay line is sampled at a rate which is a reciprocal of an integer times the delay line stepping rate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-30 | 1979-09-29 | 1980-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-30 | 1983-09-29 | 1984-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-30 | 1987-09-29 | 1988-03-30 | $7700.00 | Window Closed / Lapsed |