Latest versions of the 3GPP AMR reference implementation decoder/encoder
commandline tools compiled for AmigaOS4.

amrnb 7.0.0:
http://www.3gpp.org/ftp/Specs/html-info/26104.htm

amrwb 7.1.0:
http://www.3gpp.org/ftp/Specs/html-info/26204.htm

Usage:

Encoding:
sox test.wav -r 8000 test.sw
amrnb-encoder test.sw test.amr

Decoding:
amrnb-decoder test.amr test.sw
sox -r 8000 test.sw test.wav