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AMR file format

File extension
.amr
File category
Description
AMR is a compressed file format that functions to enhance speech coding and it consists multiple sampling rates narrow band devices used in encoding or decoding. Recording of AMR files can be done using mobile phones. For video and audio files to play at the same time or accomplish random access memory, one can utilize the 3GPP format. 160 20- millisecond samples embedded in each frame are coded using AMR using ACELP, DTX, VAD and CNG. Recorded AMR files can be converted into other files allowing their use and for them to be distributed.
Technical details
AMR has the ability of encoding signals of ranging from 4.75 to 12.2 kbit/s with quality that begins at 7.4 kbit/s.3GPP took up file format in 1999. It is a method that is utilized by GSM and UMTS, it is uses link adaptation to select one of the eight different bit rates. Link adaptation is optimized by AMR with the best codec devices that exist for it to be used by radio channels and capacity requirements. This only works if the connection is good enough to prevent the loss of audio quality.
Programs
Apple QuickTime
Realplayer
VLC media Player
Main program
Audacity
Developer
3rd Generation Partnership Project (3GPP)
MIME type
audio/amr