[pulseaudio-discuss] Mono Upmixing Only

Tanu Kaskinen tanuk at iki.fi
Fri Apr 5 09:49:43 PDT 2013

On Thu, 2013-04-04 at 09:41 +0600, Alexander E. Patrakov wrote:
> 2013/4/3 Tanu Kaskinen <tanuk at iki.fi>:
> > On Wed, 2013-04-03 at 10:20 +0100, Carl Gridley wrote:
> >> Wow, wasn't expecting code so quickly - thanks!
> >>
> >>
> >> I've been away for a bit. Is this working and done? Do I need to get
> >> PA 3 and a patch on my system or is it all good and in the queue for
> >> an offical release in the future?
> >
> > You need to apply the patch yourself, because my solution was not
> > considered good. It seems that this was only discussed in IRC, not on
> > the mailing list. A bug report has been filed, which contains the
> > explanation why the solution was not accepted:
> > https://bugs.freedesktop.org/show_bug.cgi?id=62588
> I'd say that the "no should mean no" argument is at least incomplete,
> in the sense "more discussion is needed". First, did the opponents
> present a use case when a pure "no" (with all associated side effects)
> would yield the correct result for all use cases?

No, use cases were not presented, and it might be that the strict
interpretation of "no" is not useful for anyone (except for those who
just don't happen to play any mono streams). I still agree with the
opinion that no should mean no, without exceptions. There are better
solutions than changing the semantics of the "no" option.

> Second (semi-trolling, don't take too seriously) remixing by channel
> copying and linear summation is so old-school! No modern 5.1 receiver
> does it by default when fed a stereo signal over SPDIF or HDMI. They
> have a US-patented upmixing algorithm from Dolby inside, using Z
> transformers and even non-linear elements, and most so-called "stereo"
> records are produced with that "matrix decoder" in mind. So, once this
> fancy upmixer is completely reverse-engineered, it should be an option
> at least in the countries where the patent is invalid. And yes, this
> does mean that the "enable-remixing" option is a misnomer, as it is
> not a boolean.

Yes, I agree that a boolean option isn't good.


More information about the pulseaudio-discuss mailing list