[MPlayer-dev-eng] New resampler implementations?

[Dominik 'Rathann' Mierzejewski]

On Thursday, 04 November 2004 at 23:40, Svante Signell wrote:
> Thank you very much for your input and interest. I was just about to
> assign this subject to a MSc student and maybe even doing some hacking
> myself. Of course there are other applications in need for good
> resampler implementations, both in software and hardware. Lets allocate
> the resources where interest is.

Cut the irony level, please. With so much going on lately, the developers
are up to their necks working (not only on MPlayer). It may take more than
a week to answer such mails. This one might also have been overlooked,
given the volume of traffic in this mailing list. I'm no expert on this,
but I'll try to answer as best as I can.

> On Fri, 2004-10-29 at 08:05 +0200, Svante Signell wrote:
> > Hello,
> > 
> > Seing the thread '[PATCH] fix for -srate bug' and jumping into that
> > discussion was maybe not a good idea. Now I'm starting a new thread. 

BTW: you didn't start a new thread. You just replied within the old one.
It got lost.

> > Q1) Is there any interest in alternate implementations of resamplers for
> > mplayer? If so I would like to try some ideas I have.

You're of course welcome to submit a patch implementing a new audio filter.

> > Q2) How does the interface look like in mplayer? Any code example?

Take a look at any audio filter code. There are some docs in DOCS/tech,
too.

> > Q3) Which rate conversions? 44.1kHz to 48 kHz and vice versa?

Actually any rates should be supported.

> > Q4) Has anybody made an exact, i.e. a rational number conversion?

Not that I know of.

> > Q5) Which algorithms are used in libsamplerate, mplayer, lame etc?

Lavc resampler uses sinc with a Blackman-Nuttall window. MPlayer's - I
don't know, but look at the code or wait for someone else to answer. Also
see the recent discussion.

R.

-- 
MPlayer RPMs maintainer: http://greysector.rangers.eu.org/mplayer/
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 We stand between the darkness ... and the light."
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