KR970002850A - 음성신호의 잡음저감방법 - Google Patents

음성신호의 잡음저감방법 Download PDF

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KR970002850A
KR970002850A KR1019960025902A KR19960025902A KR970002850A KR 970002850 A KR970002850 A KR 970002850A KR 1019960025902 A KR1019960025902 A KR 1019960025902A KR 19960025902 A KR19960025902 A KR 19960025902A KR 970002850 A KR970002850 A KR 970002850A
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speech signal
noise
signal
input
noise suppression
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KR1019960025902A
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조셉 찬
마사유끼 니시구찌
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이데이 노브유끼
소니 가부시끼가이샤
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Publication of KR970002850A publication Critical patent/KR970002850A/ko

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    • 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
    • G10L21/00—Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
    • G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
    • G10L21/0208—Noise filtering
    • 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
    • G10L21/00—Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
    • G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
    • G10L21/0208—Noise filtering
    • G10L21/0216—Noise filtering characterised by the method used for estimating noise
    • G10L21/0232—Processing in the frequency domain
    • 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
    • G10L21/00—Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
    • G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
    • G10L21/0208—Noise filtering
    • G10L21/0264—Noise filtering characterised by the type of parameter measurement, e.g. correlation techniques, zero crossing techniques or predictive techniques
    • 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
    • G10L25/00—Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00
    • G10L25/03—Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00 characterised by the type of extracted parameters
    • G10L25/18—Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00 characterised by the type of extracted parameters the extracted parameters being spectral information of each sub-band
    • 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
    • G10L25/00—Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00
    • G10L25/27—Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00 characterised by the analysis technique
    • G10L25/30—Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00 characterised by the analysis technique using neural networks
    • 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
    • G10L25/00—Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00
    • G10L25/90—Pitch determination of speech signals

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  • Engineering & Computer Science (AREA)
  • Human Computer Interaction (AREA)
  • Quality & Reliability (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Audiology, Speech & Language Pathology (AREA)
  • Computational Linguistics (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Compression, Expansion, Code Conversion, And Decoders (AREA)
  • Noise Elimination (AREA)
  • Filters That Use Time-Delay Elements (AREA)

Abstract

입력음성신호가 큰 피치강도를 가질때 소정대역의 억제를 금지하도록 하는 음성신호에서의 잡음저감방법이 제공된다. 잡음저감방법은 신호특성계산부, adj계산부(32), CE 및 NR 값 계산부, Hn값 계산부, 스펙트럼수 정부를 주요부로 가지는 장치에 의해 수행된다. 신호특성계산부는 입력음성신호의 피치강도를 구한다. adj계산부는 피치강도에 따라 adj값을 구한다, CE 및 NR값 계산부는 피치강도에 따라 NR값을 구한다. 그 다음 Hn값 계산부는 NR값에 따라 Hn값을 구하고, 입력음성신호의 잡음억제율을 설정한다. 스펙트럼수정부(10)는 잡음억제율에 기초하여 입력음성신호의 잡음을 줄인다.

Description

음성신호의 잡음저감방법
본 내용은 요부공개 건이므로 전문내용을 수록하지 않았음
제1도는 본 발명에 따른 음성신호의 잡음저감방법이 적용된 잡음저감장치의 요부를 나타내는 블록도이다. 제2도는 잡음저감장치에 제공된 프레임부에서 수행되는 프레임처리를 보여주는 설명도이다.

Claims (11)

  1. 입력되는 음성신호의 소정의 주파수대역을 억제하는 필터를 가지는 음성부호화장치에 음성신호를 공급하는 음성신호의 잡음저감방법에 있어서, 상기 소정의 주파수대역에 있어서의 잡음억제량을 작게하도록 주파수 특성이 제어되는 것을 특징으로 하는 음성신호의 잡음저감방법.
  2. 제1항에 있어서, 상기 필터는 상기 입력음성신호의 피치강도에 따라서 잡음억제량이 변화하는 것을 특징으로 하는 음성신호의 잡음저감방법.
  3. 제2항에 있어서, 상기 잡음억제량은 상기 입력음성신호의 고역통과측의 잡음억제를 작게하도록 변화하는 것을 특징으로 하는 음성신호의 잡음저감방법.
  4. 제1항에 있어서, 상기 소정의 주파수대역은 음성신호의 저역통과측에 위치하고, 잡음억제량은 상기 입력 음성신호의 저역통과측에서 잡음억제를 작게하도록 변화하는 것을 특징으로 하는 음성신호의 잡음저감방법.
  5. 입력음성신호의 소정의 주파수대역을 억제하는 필터를 가지는 음성부호화장치에 음성신호를 공급하는 음성신호의 잡음저감방법에 있어서, 상기 입력음성신호의 피치강도에 따라서 잡음억제를 행할때, 각 주파수 대역마다의 신호레벨과 잡음레벨과의 비에 대하여 잡음억제특성을 변화시키는 것을 특징으로 하는 음성신호의 잡음저감방법.
  6. 제5항에 있어서, 상기 잡음억제특성은 잡음억제량이 상기 피치강도가 클때에 작아지도록 제어되는 것을 특징으로 하는 음성신호의 잡음저감방법.
  7. 입력음성신호의 소정의 주파수대역을 억제하는 필터를 가지는 음성부호와 장치에 음성신호를 공급하는 음성신호의 잡음저감방법에 있어서, 상기 입력음성신호의 음성구간과 잡음구간의 판별을 행하기 위해, 잡음억제특성을 결정하는 각 파라미터를 뉴럴네트워크에 입력하는 것을 특징으로 하는 음성신호의 잡음저감방법.
  8. 제7항에 있어서, 상기 뉴럴네트워크에 입력되는 파라미터는 상기 입력음성신호의 자승평균제곱근 및 추정 잡음레벨로서 유지되는 것을 특징으로 하는 음성신호의 잡음저감방법.
  9. 입력음성신호의 소정의 주파수대역을 억제하는 필터를 가지는 음성부호화장치에 음성신호를 공급하는 음성신호의 잡음저감방법에 있어서, 잡음억제특성에 의거하여 처리되는 최대억제량은 ㏈영역에서 선형적으로 변화하는 것을 특징으로 하는 음성신호의 잡음저감방법.
  10. 입력음성신호의 소정의 주파수대역을 억제하는 필터를 가지는 음성부호장치에 음성신호를 공급하는 음성신호의 잡음저감방법에 있어서, 상기 입력음성신호의 피치강도가 신호레벨의 피크를 선택하여 얻어지는 피치위치의 근방에서의 자기상관을 계산하는 것으로 구하는 단계와, 상기 피치강도에 의거하여 상기 잡음억제 특성을 제어하는 단계를 포함하는 것을 특징으로 하는 음성신호의 잡음저감방법.
  11. 입력음성신호의 소정의 주파수대역을 억제하는 필터를 가지는 음성부호화장치에 음성신호를 공급하는 음성신호의 잡음저감방법에 있어서, 상기 입력음성신호에 관한 프레임처리는 당해 음성신호의 특징을 나타내는 파라미터의 산출용 프레임과 산출된 파라미터로 스펙트럼의 수정을 행하는 프레임과로 각각 독립하여 행하여지는 것을 특징으로 하는 음성신호의 잡음저감방법.
    ※ 참고사항 : 최초출원 내용에 의하여 공개하는 것임.
KR1019960025902A 1995-06-30 1996-06-29 음성신호의 잡음저감방법 KR970002850A (ko)

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JP95-187966 1995-06-30
JP18796695A JP3591068B2 (ja) 1995-06-30 1995-06-30 音声信号の雑音低減方法

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US (1) US5812970A (ko)
EP (1) EP0751491B1 (ko)
JP (1) JP3591068B2 (ko)
KR (1) KR970002850A (ko)
CA (1) CA2179871C (ko)
DE (1) DE69627580T2 (ko)
ID (1) ID20523A (ko)
MY (1) MY116658A (ko)

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US5812970A (en) 1998-09-22
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EP0751491A2 (en) 1997-01-02
JPH0916194A (ja) 1997-01-17
EP0751491B1 (en) 2003-04-23
MY116658A (en) 2004-03-31
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