[flac-dev] WAVEFORMATEXTENSIBLE_CHANNEL_MASK is not described

[Martin Leese]

On 7/16/15, Martin Leese <martin.leese at stanfordalumni.org> wrote:

> Martijn van Beurden wrote:
>> 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 tried to find the specific SMPTE/ITU-R
recommendation on channel order.  I found a
reference to "ITU-R BR.138", but this is not
available from the ITU-R Recommendations
website.  Does anybody have a copy of this?

I found lots of places which state the
SMPTE/ITU-R recommendation on channel
order.  But all these are only for 5.1, and
are the usual front left, front right, front center,
LFE, surround left, surround right.  I therefore
suspect the SMPTE/ITU-R recommendation is
only for 5.1.

With this in mind, I now propose the following
wording in the FLAC spec:
0000-0111 : (number of independent channels)-1. The channel assignment
and order is defined through the WAVEFORMATEXTENSIBLE_CHANNEL_MASK
FLAC tag. If no WAVEFORMATEXTENSIBLE_CHANNEL_MASK is present, the
channel assignment and order follow SMPTE/ITU-R recommendations (where
defined) and are as follows:

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