The AMR file extension is a compressed audio format widely used in mobile telephony. These files are used for voice optimization. AMR files efficiently compress speech audio for VoIP applications.
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The AMR file extension is a compressed audio format widely used in mobile telephony. These files are used for voice optimization. AMR files efficiently compress speech audio for VoIP applications.
AMR was developed by 3GPP for GSM and uses ACELP coding for toll-quality speech starting at 7.4 kbit/s. AMR files come in AMR-NB and AMR-WB variations. Programs like VLC media player, FFmpeg, and Audacity with FFmpeg can convert AMR files to other formats. AMR consists of multi-rate narrowband speech codecs that encode narrowband signals at 4.75-12.2 kbit/s. To accomplish synchronization AMR utilizes the 3GPP format. Each AMR frame contains 160 20-millisecond samples.
VLC Media Player
QuickTime Player
Audacity