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<p>Thanks for the info !</p>
<p>Then I have a question. What kind of mixer algorithms can be used
to mix 3 different channel together on an embedded system ?</p>
<p>I've used this one but it's not THAT good: (chan1 + chan2 +
chan3) / 3</p>
<p>The output signal may peak or be buggy some times.<br>
</p>
<p>For your information, I'm using an ARM M4F with Opus configured
like this (40ms, 16kHz, 16 bitrate, 0 compres).</p>
<p><br>
</p>
<p>Kind regards,</p>
<p>Andrew<br>
</p>
<div class="moz-cite-prefix">Le 06/04/2022 à 08:36, Sampo Syreeni a
écrit :<br>
</div>
<blockquote type="cite"
cite="mid:alpine.DEB.2.21.2204060925220.47345@lakka.kapsi.fi">On
2022-04-06, Ulrich Windl wrote:
<br>
<br>
<blockquote type="cite">Incidentially I came across a Dolby Atmos
demo that had about 118 channels wirh 24bit audio at 48kHz, all
in one huge WAV file yesterday.
<br>
</blockquote>
<br>
Is that even a legitimate encoding?! What the fuck.
<br>
<br>
<blockquote type="cite">When I tried to play that (in plain
stereo) with audiacity, even my fast computer (i7 at 4GHz) had
dropouts. So I can imagine that decoding a large number of
channels and mixing those seems to be a bad idea.
<br>
</blockquote>
<br>
It is. Which is why my favourite ambisonics exists (sales pitch):
it's a principled and nigh entropically speaking optimum way to
fold down a static central soundfield down to a number of
channels. Third order, so sixteen channels, seems to be upto the
task for *any* central isotropic soundfield at all, and the system
yields to static optimization.
<br>
<br>
I cannot for the life of me understand why Atmos exists. Except
for patent patent law or something like that. If it was used to
express a live gaming or augmented reality setup, with arbitrary
auditory parallax, I could get the point. But that's not what
Atmos or even Dolby AC-4 are about. They just encode a static
scene -- in a way *much* more complicated and heavier on the
processor than a "simple" third degree periphonic ambisonic HOA
signal set would be, and in a manner not amenable to low resource
optimizations in surround sound. The object based encoding simply
seems stupid and superfluous.
<br>
</blockquote>
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