[Spice-devel] [PATCH] make celt to be optional

[Alexander Larsson]

On Tue, 2012-06-12 at 14:31 +0400, Michael Tokarev wrote:
> On 12.06.2012 13:15, Alexander Larsson wrote:
> []
> > Its not incompatible, like I i said in my "(Well, .." part above. But
> > what it means is that it will send audio as PCM instead of compressing
> > it. This is much larger, and will cause anyone using the debian spice
> > client to connect to a spice server (even one that supports celt) to use
> > much more bandwidth due to this. Its not very obvious that the reason
> 
> Why do you think it is really that bad?  When used in a LAN, bandwidth
> doesn't matter, and it will even work a tiny bit better due to less
> cpu usage for encoding/decoding.  It may matter for slow/long Internet
> links, but these are much less important for audio.  Also, audio does
> not come alone usually (except of a few windows sounds), it usually
> comes together with video (ie, movies etc), which has their own
> requiriments which are much stronger than even raw audio.
> 
> I'm not saying celt or other codec is bad or not needed, something
> is definitely worth to have to be able to transmit audio cheaply,
> but it is not the first priority thing for sure.
> 
> Much more important is to have good visual expirence, and this is what
> spice is all about, and this is something what is not changed by this
> patch.
> 
> Do you not agree?

I don't really agree. Its true that if you have unlimited bandwidth,
then bandwidth doesn't matter. But I don't think in practice this is
true, as bandwidth always has some limits in reality. Its possible that
it works fine in some situations, but its also quite possible that its a
deal-breaker in some others, and we have no data to substantiate the
claim that it doesn't matter (in fact, it seems unlikely since the
developers spent time and energy to implement audio compression).

Spice is very much about more than just pixels, that it does more than
graphics (usb, sound, audio-video sync, clipboard, etc) is an important
part of why Spice is better than other solutions. In fact, our support
of movies by using compressed video and audio is a pretty important
selling point of spice.

The main thing I disagree with this change is that you change how spice
works, making act differently than its creators intended, due to a
packaging technicallity. You decide that spice users are not interested
in low-bandwidh audio, without asking and without telling them. (I'm
sure it'll be mentioned somewhere, but its unlikely that most users will
see it.)