13 Jun
2005
13 Jun
'05
4:18 p.m.
Erik de Castro Lopo wrote:
Firstly I see that its basically a drum machine. Drum
hits are
relatively we behaved when linear sample rate converison is used.
It looks like a drummmachine, but that's not the goal of the project. I use
vocal, guitar, bass and drum tracks. I know a Jackbeat user who does similar
things. Samples can be pretty long.
Secondly, why don't you just do the sample rate
conversion on
sample load time and sort the converted version in memory.
This will mean that you do the conversion once for each drum
sound rather than on all tracks all the time?
That's what I did at first, but for several reasons I switched to realtime
conversion. One the most important reason is rate shifting, which is performed
by the sample rate converter according to the following statement :
ratio = jack_framerate / sample_framerate / pow (2, pitch / 12);
The "pitch" is a per track value that the user can change at anytime.
As you can see I use libsamplerate (or my homemade converter) to perform both
sample rate conversion and cheap pitch shifting in a single operation. AFAIK
there just is no difference between a sample rate converter and a so-called
"rate-shifter". Or please tell me what the difference is...
--
og