[LAU] Sample rate conversion for media playback

Darren Landrum darren.landrum at sbcglobal.net
Wed Apr 9 21:16:29 EDT 2008


James Cameron wrote:
> G'day Darren,
> 
> What is supposed to happen is that the application that is playing the
> audio should set the sound card to the sample rate of the audio source.
> It does this by issuing commands to the sound card driver, or sound
> server.
> 
> If the sound card is forced to another rate, then sure, you'll get pitch
> and speed changes.

Well, that would explain a few things, as I have to adjust the rate 
manually through Alsamixer, and 44.1 and 48khz are the only options this 
card supports. It's the same deal on the Windows side, though, and I can 
still play back 22.05khz stuff back with no issues. It's possible that 
the factory drivers from Emu are doing the SRC on the fly in the 
background when needed.

> Probably need more information ... are you using ALSA or OSS drivers
> for the sound card, and are you using an audio sound server like Jack,
> Esound, Pulseaudio?

I'm using ALSA 1.0.16 Stable, compiled myself from sources.

-- Darren





More information about the Linux-audio-user mailing list