[MPlayer-dev-eng] [BUG] surround audio plugin broken

[D Richard Felker III]

On Mon, Jan 06, 2003 at 11:08:14AM +0800, Anders Johansson wrote:
> Hi,
> 
> > Hi,
> > 
> > > > > Disagree, resampling when the movie is 48000 hz and the soundcard only
> > > > > supports 44100 should be done by default, just like -vop scale is
> > > > > auto-inserted when the output device is rgb. Otherwise the output is
> > > > > just wrong.
> > > > 
> > > > yep. but for example automatic resampling of 44100 to 44098 is just dumb.
> > > > (and slow and causes big delay and whatever)
> 
> Perhaps the sloppy switch in resample should be enabled by default.

What exactly does sloppy do? I was under the impression that it was
the same as the old aop-resample, which gave 44250 or 44015 or some
such nonsense when 44100 was requested. Not only does this sound a bit
bad to a trained ear (i.e. not mine :), but it also messes up the
framerate by a significant amount which can be bad if you want exactly
one frame per refresh.

> > this way we lose conversions helped by the codecs (examples: liba52's
> > float2int, channels downsampling, mp3lib's half or quarter freq decoding,
> > mono decoding of stereo sterams, stereo decoding of mono streams).
> > but this way we could ask the soundcard to accept the codec's native format,
> > and do the conversion only if it cannot be done. if both codecs & ao
> > supports float, then prefer float in filters, otherwise if both codec & ao
> > are integer, then don't convert it to & back from float, it just eats cpu.
> > if the user wants hi-fi quality, he can still force float filters on
> > commandline.
> 
> Should I make the filters convert to float depending on the -format switch
> rather than depending on CPU speed perhaps?

I think Arpi was saying (and I agree) that filters should NEVER
convert to float and back unless explicitly requested, or unless a
filter appears in the chain which cannot handle integer data.

Rich