- Extension
- .amr
- .m4r
- Format
- Binary
- Binary
- Category
- Audio
- Audio
- Developer
- Nokia
- Apple Inc.
- Description
- An AMR file is an audio file saved in a compressed audio format developed by Ericsson. It is used by many 3G cell phones for voice recordings such as MMS messages. AMR files incorporate the Algebraic Code Excited Linear Prediction (ACELP) algorithm, which is designed to efficiently compress human speech audio.
- M4R is an iTunes ringtone file that stores mono channel audio. They are identical to the M4A format files only that they are correctly used for ringtones.
- MIME Type
- audio/amr
- audio/x-m4r
