FR2277398A1 - Speech recognition system using vocoder - has adaptive digital filter extraction circuit for low pass filter and analyser - Google Patents

Speech recognition system using vocoder - has adaptive digital filter extraction circuit for low pass filter and analyser

Info

Publication number
FR2277398A1
FR2277398A1 FR7520878A FR7520878A FR2277398A1 FR 2277398 A1 FR2277398 A1 FR 2277398A1 FR 7520878 A FR7520878 A FR 7520878A FR 7520878 A FR7520878 A FR 7520878A FR 2277398 A1 FR2277398 A1 FR 2277398A1
Authority
FR
France
Prior art keywords
filter
analyser
vocoder
pass filter
peaks
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
FR7520878A
Other languages
French (fr)
Other versions
FR2277398B3 (en
Inventor
Richard Jerome Schulman
Mark Joel Schneider
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by International Standard Electric Corp filed Critical International Standard Electric Corp
Publication of FR2277398A1 publication Critical patent/FR2277398A1/en
Application granted granted Critical
Publication of FR2277398B3 publication Critical patent/FR2277398B3/fr
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10L—SPEECH ANALYSIS TECHNIQUES OR SPEECH SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING TECHNIQUES; SPEECH OR AUDIO CODING OR DECODING
    • G10L19/00—Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
    • G10L19/04—Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis using predictive techniques

Landscapes

  • Engineering & Computer Science (AREA)
  • Computational Linguistics (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Audiology, Speech & Language Pathology (AREA)
  • Human Computer Interaction (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Filters That Use Time-Delay Elements (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

The vocoder has an adaptive digital filter providing a digital residual, which is supplied to an extraction circuit for the fundamental, provided by a squaring circuit connected to the output of the filter, so as to square the residual. A digital low pass filter is connected to the output of the squaring circuit and an analyser for the fundamental is connected to the output of this filter to locate the peaks etc in the filter output signal and to determine the time interval between consecutive peaks, so as to provide an output signal equal to the period of the peaks. The analyser has a search area displaceable in time and a time variable threshold amplitude for locating the peaks. Pref. the low-pass filter has a divider connected to a series register stage, an adder stage and a second divider.
FR7520878A 1974-07-03 1975-07-03 Speech recognition system using vocoder - has adaptive digital filter extraction circuit for low pass filter and analyser Granted FR2277398A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US48548774A 1974-07-03 1974-07-03

Publications (2)

Publication Number Publication Date
FR2277398A1 true FR2277398A1 (en) 1976-01-30
FR2277398B3 FR2277398B3 (en) 1979-02-23

Family

ID=23928370

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7520878A Granted FR2277398A1 (en) 1974-07-03 1975-07-03 Speech recognition system using vocoder - has adaptive digital filter extraction circuit for low pass filter and analyser

Country Status (1)

Country Link
FR (1) FR2277398A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2351467A1 (en) * 1976-05-15 1977-12-09 Licentia Gmbh PROCESS FOR DETERMINING THE FUNDAMENTAL PERIOD OF A VOICE SIGNAL USING THE DIFFERENTIAL SIGNAL DELIVERED BY PREDICTIVE VOCODERS.

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2351467A1 (en) * 1976-05-15 1977-12-09 Licentia Gmbh PROCESS FOR DETERMINING THE FUNDAMENTAL PERIOD OF A VOICE SIGNAL USING THE DIFFERENTIAL SIGNAL DELIVERED BY PREDICTIVE VOCODERS.

Also Published As

Publication number Publication date
FR2277398B3 (en) 1979-02-23

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Legal Events

Date Code Title Description
ST Notification of lapse