[FFmpeg-user] How can I convert mpeg2 5.1 audio to ac3?
adf.lists at gmail.com
Tue Nov 11 13:29:09 CET 2014
Carl Eugen Hoyos wrote:
> Where I live all movies are broadcast PLII.
Ahh, I didn't realise it was still so popular.
> As said MythTV contains a PLII decoder (filter).
So it does, I couldn't find it when I first looked.
Doesn't seem very much compared to the quite complicated looking
descriptions of what a "real" decoder supposedly does.
float lt = *samples++;
float rt = *samples++;
bufs->l[ic] = lt;
bufs->lfe[ic] = bufs->c[ic] = (lt+rt) * m3db;
bufs->r[ic] = rt;
// surround channels receive out-of-phase
bufs->ls[ic] = (rt-lt) * 0.5;
bufs->rs[ic] = (lt-rt) * 0.5;
I don't pretend to know what should happen - but it's obvious that that
leaves the S in the fronts - but then you said your receiver did
too. I wonder if all receivers would.
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