On 04/04/2012 00:13, Sampo Syreeni wrote:
On 2012-04-03, Richard Dobson wrote:
Well, we don't need to get hyper-paranoid about it. Apple have defined
channel IDs for WXYZ, which goes no further than make it possible to
create a 1st-order CAF file.
Agreed. And whatever ambisonic related patents there are for first
order, they will have run out by now.
CAF is not closed, the spec is fully open and documented.
On the other hand, Apple hasn't placed any of its coding related
software patents into the open domain, here, and CAF is rather new. Most
of the technology could be challenged because it's a derivative of EA
IFF and then Microsoft RIFF (WAV) derived (even EBU's 64-bit WAV
derivative is part of the open, prior art).
?? what patents? You are tilting at windmills. CAF is a file format
(more precisely a container format), a standard to be followed, not a
device (much less an algorithm) that can be patented. Did you think
WAVE was somehow patented? Or XML for that matter? OK, if you put
something such as an mp3 stream inside a file, then technically you need
a licence to encode/decode it; but there can be no patent attached to a
file format per se.
See here for all you need to know about CAF (including how to implement
it on other platforms). And note it is extensible in just the same way
WAVEX is:
https://developer.apple.com/library/mac/#documentation/MusicAudio/Reference/CAFSpec/CAF_intro/CAF_intro.html
You can download it as a pdf. You will find no reference to a patent
anywhere.
Richard Dobson
_______________________________________________
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound
