Re: [Audacity-devel] Forcing project rate to rate of imported file

[Michael S. <msc...@gm...>]

On Tue, 06 May 2008 22:43:56 +0100, Richard Ash wrote:

> On Tue, 2008-05-06 at 11:37 +0200, Michael Schwendt wrote:
> > On Tue, 06 May 2008 03:40:13 +0100, Gale Andrews wrote:
> > > " Fix: Make all platforms consistently force Project Rate to the rate of
> > > imported file irrespective whether that rate is supported or not.
> > > Currently this does not work on Windows and results vary on Linux. Is
> > > Michael's issue "1.3.3-beta and newer fill the "Project Rate" combo box
> > > with several invalid frequencies, most likely picking them from a
> > > hardcoded list without making sure the audio hardware can handle them"
> > > related? When done, add a Preference to always have Project Rate remain
> > > as per its Default Sample Rate Preference setting irrespective of the
> > > file being imported (this is currently "not aiming for 1.4.0")."
> > > 
> > > I assume "Michael's issue" is resolved now, and the stated problem in
> > > the first sentence of the above seems to be fixed for me.
> "Micheal's issue" never worked the way he thought it did, the problem
> was that the code assumed the set of supported sample rates was the same
> for record and playback, which it seems is often not true. This has
> indeed been fixed for ages.
> 
> > It appears to work since post 1.3.4-beta from cvs, i.e. some time around
> > January 2008. Earlier, there would be an error dialog for almost every
> > project rate in the list, saying that playback can't handle the rate.
> > (And yes, that was not due to missing resampling, but PortAudio weirdness.)
> NO, it was because audacity thought playback would work without
> resampling, but in fact wouldn't. Note that what audio I/O device you
> select is critical for these tests.

:)

I'm sure we talk about the same thing.
It doesn't really matter what happens under the hood (I've developed
low-level audio drivers before, so I'm somewhat familiar with the
requirements of audio I/O interface layers). All that counts is what
behaviour the Audacity user is confronted with. And for me it was that
since 1.3.3-beta I could not even load and play a pretty standard 44.1 kHz
WAV file. Discussing it in the forum lead to the suggestion that I have
to find a supported sample rate myself, which sounded like a highly
questionable suggestion. The user doesn't care at all whether the audio
hardware possibly expects 48 or 96 kHz data only and requires the software
to apply resampling in order to support other frequencies.
It's also clear that project rate and output sample rate may differ.
The basic test only was about importing and playing a file.

-- 
Michael Schwendt <msc...@fe...>
Fedora release 8 (Werewolf) - Linux 2.6.23.15-137.fc8
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