.AMR File Extension
File TypeAdaptive Multi-Rate Codec File
This file is saved in a binary format, which requires a specific program to read its contents.
Compressed audio format developed by Ericsson; used by many 3G cell phones for voice recordings such as MMS messages; incorporates the Algebraic Code Excited Linear Prediction (ACELP) algorithm, which is designed to efficiently compress human speech audio.
NOTE: AMR files may be saved in either the AMR-NB (Narrowband) or AMR-WB (Wideband) format. Wideband audio supports a broader frequency range and therefore provides better sound quality.