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 - Submitted by
- 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
- Description
- BOF: (offset 4): ftypM4A VAR: alac{0-72}alac
- Provenance
- 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#
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
-
V123
- Release date
- 9 June 2026
-
Updated
Apple Lossless Audio Codec: . Submitted by Preservica.
-
V74
- Release date
- 31 March 2014
-
Updated
Apple Lossless Audio Codec: Improved specificity of BOF signature sequence offset.
-
V72
- Release date
- 12 November 2013
-
Added format
Apple Lossless Audio Codec: Outline Entry Added.
-
Added signature
Apple Lossless Audio Codec: Signature developed through PRONOM Research.