I'm really enthousiastic about csound: I'm building my own "virtual analog guitarsynth", and the progress is really nice: best programmable sound environment in the universe, is my opinion.
I use portaudio for audio in/ out, but want coreaudio to improve performance.
QuteCsound lets me change that in the configuration window, but I dont get any inputsignal, whatever adcx I choose
When I choose "adc99" csound tries to open adc99 and gives no error! so I cant find out which number I should use.
Default input, determined by host system, (-iadc) gives no signal
Does anyone know what I'm doing wrong?
thanks in advance!
hardware: MacBook, MacOsX 10.5.8, 2ghz IntelCoreDuo, 4GB ram, QuteCsound 0.4.4, Csound 5.5
Re: Problem: How do I get realtime audio input from Core audio?
Csound actually communicates with CoreAudio via PortAudio. So if you're using PortAudio, you're using CoreAudio.
thanks for the response
thanks for the response .mmb!,
"..communicates with CoreAudio via PortAudio": mmh.. as long as this doesn't slow down the processing, this is fine ofcourse..
Csound5 uses nearly half my processorpower with doing nothing: I wonder if there's a good reason for this.
The actual soundprocessing is fast enough, but running CSound idle with *no instruments* causes my laptop to turn on its propellors..
My guess is, that csound interrupts the computer at audio-rate, and has a large stack to stack/unstack.
re: thanks for the response
Are you on an Intel machine? This could be a problem with denormals. Basically, Intel processors work harder at calculating low (non-zero) numbers than high ones. But if you actually don't have any instruments turned on, I don't know why this would happen, unless you have an always-on global reverb or some other feedback-type effect going on. If this is the case, check out the denorm opcode.
Also, I believe the processing is done at k-rate.
it isnt the "low value
it isnt the "low value floating point issue", I've read about it.
It is just so that an empty csound score + instrument doing nothing at all, soaks up so much processing power. It makes me wonder if this is normal. Perhaps it is, and i'm too picky.
I'm in no hurry, i'm primarily a guitar player who likes to experiment with sound in his sparetime.. but i'm interested in using csound live on stage in the future.
Thanks for the thoughts spend sofar!
Idle time shouldn't be expensive
I don't have a Mac, so I can't comment from direct experience, but on my systems (BeOS and Linux) an idling Csound doesn't usually soak up much processing power, except under one condition: using small buffers on my old, slow BeOS machine to get snappy low-latency output.
I found that I needed to use the -B32 option to keep the latency unnoticeable, but this does make it burn up about 60% of the CPU while doing nothing (except outputting silence). If I double the buffer size, that drops markedly (and actually latency isn't too bad, but noticeable). With default buffer size, the load is negligible. However, looking at usage by thread (with 'top'), it's not Csound itself that's gobbling cycles, but the audio server that handles the stream of buffers.
It was harder to check on my Linux system, because the graphic usage monitor itself eats 90% of the processor power!!! [Good ol' linux...] I can use 'top' there too, though, and that seems to show fairly low overhead under all conditions.
You can probably find the 'top' program or something similar for your Mac, to see where the load actually is, but in summary I don't think you should be seeing it on a fast modern machine.