Moritz Barsnick wrote:
On Tue, Nov 11, 2014 at 12:29:09 +0000, Andy Furniss wrote:
Carl Eugen Hoyos wrote:
Where I live all movies are broadcast PLII.
Ahh, I didn't realise it was still so popular.

Where I live - Germany - the "minor" stations try to use less bandwidth
on the satellite transponders / in their bouquets, and transmit only
one AC-3 audio stream with two channels. Nevertheless, I get quite
proper surround sound from my sound system during many movies. So my
conclusion is that they use the PLII "down-mix".

(Unless that statement was a misunderstanding and we're talking about
something totally different.)

As said MythTV contains a PLII decoder (filter).
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;

That looks different from what we were looking at earlier in the thread
(and far too simple). Carl Eugen had pointed out this file:

https://github.com/MythTV/mythtv/blob/master/mythtv/libs/libmythfreesurround/el_processor.cpp

Agh, thanks for that - the code I posted is from myth, but obviously I don't know if it's ever used.

For some reason this thread has split into two for me and I didn't see the other bit.

_______________________________________________
ffmpeg-user mailing list
ffmpeg-user@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

Reply via email to