1 Apr
2006
1 Apr
'06
8:20 a.m.
On Sat, Apr 01, 2006 at 10:49:20AM +0100, Simon Jenkins wrote:
On Thu, 2006-03-30 at 22:33 +0200, torbenh(a)gmx.de
wrote:
well... there are some soundcards which can only do one samplerate
(48k or 44k1 namely) so for this case its real resampling...
i have just found that there was a timeout value in the select()
in net_driver_wait() resulting in kernel busy waiting...
this changed the cpu usage in some unfavourable manner... i am off for
some other tests... and going back to SINC_FASTEST now...
also for the internet case i am getting quite bursty clocking an
currently dont have a way to get timestamps etc from the jack_driver to
the client. so while experimenting with this stuff, i am experiencing
resampling of 5% or so...
i am currently experimenting with the coefficients and function for the
delay locked loop controlling the resample factor...
i need all features of libsrc (slowly changing
samplerate, and resample
factors of 1.00001 or so)
Lets assume - unrealistically, but for the convenience of the
maths - a sample rate of 50kHz and a buffer size of 1000. Your
resample factor of 1.00001 or so means you need to "find" or
"lose" a sample about once every 2 seconds, and 99% of your
buffers will be precisely the same size going out as they are
coming in.
Is putting the entire stream through a resampler (especially
a "crap" one) the thing to do here? I'm wondering if there
might be a better way to gain or lose the occasional sample.
erm... Anyone?
Simon Jenkins
Bristol, UK
--
torben Hohn
http://galan.sourceforge.net -- The graphical Audio language