DECODING OF SPEECH FROM TAPE RECORDINGS (FROM CARNAHAN CONFERENCE ON CRIME COUNTERMEASURES - PROCEEDINGS, 1977, BY JOHN JACKSON - SEE NCJ-57737)

• NCJ Number: 57744
• Author(s): H R ROTHMAN
• Date Published: 1977
• Length: 5 pages
• Corporate Author: University of Kentucky
• Publication Format: Document
• Language: English
• Country: United States of America

Annotation

PROBLEMS INHERENT IN DECODING SPEECH FROM TAPE RECORDINGS ARE DISCUSSED, PARTICULARLY IN LIGHT OF THE FACT THAT SPEECH PERCEPTION IN INDIVIDUALS IS DEPENDENT ON MANY FACTORS OTHER THAN THE ANALYSIS OF THE SIGNAL AT HAND.

Abstract

THE PROCESS OF DECODING SPEECH RECORDED ON MAGNETIC TAPE PRESENTS A NUMBER OF UNIQUE PROBLEMS TO THE LISTENER/DECODER. IN NORMAL LISTENING SITUATIONS A MESSAGE THAT IS PRODUCED AND TRANSMITTED CAN BE EASILY DECODED BY A LISTENER PRESENT AT THE SCENE. IF A MICROPHONE IS SUBSTITUTED FOR THE LISTENER AND THE MESSAGE IS RECORDED, THE RESULT IS USUALLY A DIFFICULT TO DECODE RECORDING. THE NORMAL ABILITY TO DECODE SPEECH EVEN IN THE PRESENCE OF AMBIENT MASKING NOISES AND COMPETING SPEECH SIGNALS, IS CALLED THE 'COCKTAIL PARTY' PHENOMENON. THIS PHENOMENON IS DUE, IN PART, TO SOUND LOCALIZATION, A PRIMITIVE HUMAN SKILL. THIS PAPER DISCUSSES ACOUSTIC-PERCEPTUAL THEORIES OF SPEECH DECODING, VARIOUS ASPECTS OF HUMAN SPEECH PERCEPTION/DECODING IN NORMAL SITUATIONS (INCLUDING THE ROLE OF SOUND LOCALIZATION, THE RELATIONSHIP AND EFFECT OF THE COMBINED SPEECH AND AMBIENT ACOUSTIC SIGNAL TO PERCEPTION/DECODING, AND THE SPECIAL PROBLEMS INVOLVED IN DECODING SPEECH RECORDED IN FORENSIC SITUATIONS. VISUAL AND AURAL SAMPLES OF SPEECH RECORDED UNDER CONDITIONS OF LIMITED PASSBAND, AMBIENT MAKING, COMPETING SIGNALS, AND VARYING DIALECTS AND PROPER NAMES ARE ALSO DISCUSSED. GRAPHS AND REFERENCES ARE INCLUDED. (AUTHOR ABSTRACT MODIFIED--KBL)