The present document contains an electronic copy of the ANSI C code for the Adaptive Multi-Rate codec. The ANSI C code is necessary for a bit exact implementation of the Adaptive Multi Rate speech transcoder (TS 26.090
), Voice Activity Detection (TS 26.094
), comfort noise (TS 26.092
), source controlled rate operation (TS 26.093
) and example solutions for substituting and muting of lost frames (TS 26.091
The following documents contain provisions which, through reference in this text, constitute provisions of the present document.
References are either specific (identified by date of publication, edition number, version number, etc.) or non specific.
For a specific reference, subsequent revisions do not apply.
For a non-specific reference, the latest version applies.
 TS 26.074
"AMR Speech Codec; Test sequences".
 TS 26.090
"AMR Speech Codec; Speech transcoding".
 TS 26.091
"AMR Speech Codec; Substitution and muting of lost frames".
 TS 26.092
"AMR Speech Codec; Comfort noise aspects".
 TS 26.093
"AMR Speech Codec; Source controlled rate operation".
 TS 26.094
"AMR Speech Codec; Voice Activity Detection".
 RFC 3267:
"A Real-Time Transport Protocol (RTP) Payload Format and File Storage Format for Adaptive Multi-Rate (AMR) and Adaptive Multi-Rate Wideband (AMR-WB) Audio Codecs", June 2002.
Definition of terms used in the present document, can be found in TS 26.090
, TS 26.091
, TS 26.092
, TS 26.093
and TS 26.094
For the purpose of the present document, the following abbreviations apply:
American National Standards Institute
European Telecommunication Standard
Global System for Mobile communications
Random Access Memory
Read Only Memory