Format
Apple Lossless Audio Codec
Summary
- Name
- Apple Lossless Audio Codec
- Identifiers
- PUID: fmt/596
- Format type
- Audio
- Description
- Apple Lossless, also known as Apple Lossless Audio Codec (ALAC), or Apple Lossless Encoder (ALE), is an audio codec developed by Apple Inc. for lossless data compression of digital music. Apple Lossless data is stored within an MP4 container with the filename extension .m4a.
- Note
- http://www.applelossless.com/ http://alac.macosforge.org/trac/browser/trunk/ALACMagicCookieDescription.txt http://alac.macosforge.org/trac/browser/trunk/codec/ALACAudioTypes.h?rev=2#
- File extensions
-
m4a,mp4 - Source
- Digital Preservation Department / The National Archives
- Developed by
- Apple Computer, Inc.
- Supported by
- Apple Computer, Inc.
Relationships
- Has priority over
Internal signatures
Apple Lossless Audio Codec
- Note
- BOF: (offset 4): ftypM4A VAR: alac{0-72}alac
Byte sequences
- Min Frag Length
- Absolute from BOF
- Offset
- 4
- Max offset
- None
- Byte Sequence
667479704D344120- Endianness
- None
- Min Frag Length
- Variable
- Offset
- None
- Max offset
- None
- Byte Sequence
616C6163{0-72}616C6163- Endianness
- None
Changelog
-
Updated in V123
- Release date
- 9 June 2026
Apple Lossless Audio Codec: . Submitted by Preservica.
-
Updated in V74
- Release date
- 31 March 2014
Apple Lossless Audio Codec: Improved specificity of BOF signature sequence offset.
-
Added in V72
- Release date
- 12 November 2013
Apple Lossless Audio Codec: Signature developed through PRONOM Research.
Apple Lossless Audio Codec: Outline Entry Added.