Format
Adaptive Multi-Rate Audio
Summary
- Name
- Adaptive Multi-Rate Audio
- Identifiers
-
- MIME: audio/amr
- PUID: fmt/356
- Format type
- Audio
- Description
- The Adaptive Multi-Rate (AMR or AMR-NB or GSM-AMR) audio codec is an audio compression format optimized for speech coding. AMR speech codec consists of a multi-rate narrowband speech codec that encodes narrowband (200–3400 Hz) signals at variable bit rates ranging from 4.75 to 12.2 kbit/s with toll quality speech starting at 7.4 kbit/s.
- File extensions
-
amr - Source
- Digital Preservation Department / The National Archives
Relationships
- Can be contained by
Internal signatures
Adaptive Multi-Rate Audio
- Note
- Header (ASCII): #!AMR.
Byte sequences
- Min Frag Length
- Absolute from BOF
- Offset
- 0
- Max offset
- None
- Byte Sequence
2321414D520A- Endianness
- None