CAF (Core Audio Format)
More info
- Creator
- Apple
- Released
- 2005
- Type
- File format (container)
Apple's audio container from Mac OS X Tiger, built to escape the 4 GB ceiling of WAV and AIFF and to hold any format Core Audio can read.
WAV and AIFF store sizes in 32 bits, and at four gigabytes the file simply ends. For long multitrack recordings at high sample rates that is not very far. CAF, introduced with Tiger in 2005, uses 64-bit sizes and can be written so that it survives interruption: a recording that dies halfway is still readable up to the moment of the crash.
It is purely a container. Inside can be linear PCM, AAC, ALAC or anything else Core Audio understands, and the afconvert tool shuffles audio between them. Outside Apple's world CAF never caught on — the Windows side solved the same problem with RF64 — but in iOS games and Xcode projects .caf is still the extension Apple itself recommends.