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Re: [Cellar] Last call on FLAC specification

Martin Leese <martin.leese@stanfordalumni.org> Sun, 02 October 2022 19:42 UTC

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From: Martin Leese <martin.leese@stanfordalumni.org>
Date: Sun, 02 Oct 2022 13:42:03 -0600
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Subject: Re: [Cellar] Last call on FLAC specification
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On 9/30/22, Martijn van Beurden <mvanb1@gmail.com> wrote:
>
> The RF64 specification actually defines a lot more channel mask bits than
> just SPEAKER_ALL. It does also define downmixes, control samples and
> bitstreams.

On 9/30/22, Martijn van Beurden <mvanb1@gmail.com> wrote:
>
> I was looking at EBU Tech 3306-2007. See Enhancement for a PCM stereo
> down mix for example.

There appears to be two definintions of
"downmix".  The RF64 spec talks of two extra
channels included in the audio file.  What I am
pushing for is metadata which allows stereo
channels to be configured on the fly using
weighted sums of two or more channels from
the multichannel mix.  The former requires
additional audio data, the latter only requires
a small amount of metadata.

I would srongly urge for FLAC (and other file
formats) to include optional downmix metadata.

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

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