Adaptive Multi-Rate Codec File
AMR (Adaptive Multi-Rate Codec File) is a compressed audio format used by 3G cell phones for voice recordings such as MMS (Multimedia Messaging Service) messages. AMR incorporates the Algebraic Code Excited Linear Prediction (ACELP) algorithm, which was created to optimize compression of human speech data. AMR was developed by Ericsson.
Programs that open AMR files include Apple QuickTime Player, RealNetworks RealPlayer, Mobile AMR Converter and AMR Tool.