[flac-dev] WAVEFORMATEXTENSIBLE_CHANNEL_MASK is not described

[Martin Leese]

Martijn van Beurden wrote:

> Op 16-07-15 om 17:58 schreef lvqcl:
>> But this text describes only those 4 bits in frame header.
>> IMHO this sectoin should not describe WAVEFORMATEXTENSIBLE_CHANNEL_MASK,
>> it should be described somewhere in vorbis comments section.
>
> I would propose: 0000-0111 : (number of independent channels)-1.
> The channel order is defined through the
> WAVEFORMATEXTENSIBLE_CHANNEL_MASK vorbis comment, if defined. If
> no WAVEFORMATEXTENSIBLE_CHANNEL_MASK is present, the channel
> order follows SMPTE/ITU-R recommendations, which are as follows:

This looks like an excellent proposal.  I
suggest *where* in the FLAC spec the
WAVEFORMATEXTENSIBLE_CHANNEL_MASK
vorbis comment is described also needs to be
stated .  It needs be described somewhere
because it is not obvious how a single 32-bit
word should be stuffed into "a short text
comment".

The Vorbis comment could be described in the
FLAC spec under FRAME_HEADER, under
METADATA_BLOCK_VORBIS_COMMENT or
in a new section in the general spiel near the
top.  I would suggest in the general spiel.  (At
the moment, the METADATA section does little
more than point to the Ogg Vorbis I format
specification; the detail of this particular Vorbis
comment should not be in the Vorbis spec.)

Regards,
Martin
-- 
Martin J Leese
E-mail: martin.leese  stanfordalumni.org
Web: http://members.tripod.com/martin_leese/