[SDL] Re: More stupid audio questions...
Jess
sdl@lokigames.com
Sat, 05 Feb 2000 11:23:42 -0600
--------------CF4215D4FE0AD2BB042AC977
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Bill Radcliffe wrote:
> Ok - then how do apps like WinAmp manage to display power meters and such?
> They must have access to the decoded data in order to take an FFT or
> whatever and generate their displays.
thats a good question, im guessing they can somehow read the audio back from
the soundcard. It is posible to read the actual cdda data from cd but it is not
as simple as reading a file from a cd and is a lot slower.
> What would your strategy by for CDDA? How do you think WinAmp and other
> apps do it on Win32?
>
for information on te cdda format the sox source would probly be helpful. as
for reading the data from the cdrom drive on linux you might want to take a
look at cdda2wav and cdparanoia(http://www.xiph.org/paranoia/). cdda2wav
actualy includes an option to play a cd by ripping the audio data and sending
it to the soundcard. i have also used cdparanoia to do this with a pipe and sox
but its slower because it aims more at retrieveing corect data than getting it
as fast as posible. the paranoia IV library which is part of the cdparanoia
project might be useful to you, it aims at being cross-platform but currently
doesnt support much more than a few unix's.
Jess
--------------CF4215D4FE0AD2BB042AC977
Content-Type: text/html; charset=us-ascii
Content-Transfer-Encoding: 7bit
<!doctype html public "-//w3c//dtd html 4.0 transitional//en">
<html>
Bill Radcliffe wrote:
<blockquote TYPE=CITE>Ok - then how do apps like WinAmp manage to display
power meters and such?
<br>They must have access to the decoded data in order to take an FFT or
<br>whatever and generate their displays.</blockquote>
thats a good question, im guessing they can somehow read the audio back
from the soundcard. It is posible to read the actual cdda data from cd
but it is not as simple as reading a file from a cd and is a lot slower.
<br>
<blockquote TYPE=CITE>
<pre> What would your strategy by for CDDA? How do you think WinAmp and other
apps do it on Win32?</pre>
</blockquote>
for information on te cdda format the sox source would probly be helpful.
as for reading the data from the cdrom drive on linux you might want to
take a look at cdda2wav and cdparanoia(<A HREF="http://www.xiph.org/paranoia/">http://www.xiph.org/paranoia/</A>).
cdda2wav actualy includes an option to play a cd by ripping the audio data
and sending it to the soundcard. i have also used cdparanoia to do this
with a pipe and sox but its slower because it aims more at retrieveing
corect data than getting it as fast as posible. the paranoia IV library
which is part of the cdparanoia project might be useful to you, it aims
at being cross-platform but currently doesnt support much more than a few
unix's.
<p>
Jess</html>
--------------CF4215D4FE0AD2BB042AC977--