Though the alacconvert-utility seems to handle CoreAudio (CAF) files fine, the M4A ALAC-files cause it to file:
% file c.m4a
c.m4a: ISO Media, Apple iTunes ALAC/AAC-LC (.M4A) Audio
% alacconvert c.m4a c.caf
Input file: c.m4a
Output file: c.caf
Cannot determine what format file "c.m4a" is
The alac tool, originally by David Hammerton (now part of ffmpeg) used to work with just those files -- identified by the "M4A " magic-string at the beginning.
Though the
alacconvert-utility seems to handle CoreAudio (CAF) files fine, the M4A ALAC-files cause it to file:The
alactool, originally by David Hammerton (now part of ffmpeg) used to work with just those files -- identified by the "M4A" magic-string at the beginning.