hey, cool. I'll try and test it later (in about 8 hours).
Sounds like an interesting project :) On Mon, Mar 31, 2008 at 3:26 PM, Wyatt Olson <[EMAIL PROTECTED]> wrote: > Yes, I have tried all sorts of buffer sizes (all the way down to 8). I > can't see any difference in performance with any of these. As for the > source, I tool a look at mixer.c, but to be honest I am not as up to > date on my C as I would like - I have concentrated on higher level > languages for a bit too long, and have forgotten the details of these > older ones. 8-( > > As for the program, you can access it at > http://drummaster.thecave.homeunix.org/files/DrumSlave_Minimal.zip . > This only has one sample (a snare drum) for testing, which is mapped to > port 0. Other than that, it is exactly as I am using it. > > To run, unzip and use the command: > > python drum_slave.py --keyboard rock > > It should run on python 2.4 or 2.5, with any semi-recent version of pygame. > > The application is meant to be the slave for a hardware board I > developed, which talks to the computer via a serial port. To allow > testing, I added the keyboard mode, in which you can manually type the > commands which otherwise would come over the serial port. > > Once the application starts, type "0:1023" (without quotes), and hit > enter. A drum sound will play. I am measuring latency by recording the > whole thing in an audio recorder, and measuring the difference in time > between the sound of me hitting enter and the sound of the sample being > played. In my tests, it seems to average to about 65 or 70 ms, with a > maximum of about 100ms. > > As for program layout, the initialization is done in slave.py. > drum_slave.py is just the command line wrapper. Pygame Sound objects > are played in hardware/sensor.py. I don't think that anything else > would be relevant to this discussion, but it should be simple enough to > find your way around in, if you are interested - the program is not very > large. > > All my testing so far has been done on OS X. I am planning to try some > tests on Linux, once I can get a box put together. If anyone does test > this on a different platform, I would be very interested in hearing the > results, and how they compare to mine. > > Thanks for all your help! > > Cheers > > > > René Dudfield wrote: > > Hello, > > > > Do you have a link to your code? > > > > You've tried setting a really small buffer size? Like 512 or something? > > > > Have a look at src/mixer.c to see how SDL is used. > > > > cheers, > > > > > > > > On Mon, Mar 31, 2008 at 2:50 PM, Wyatt Olson <[EMAIL PROTECTED]> wrote: > > > >> Upgraded to pygame 1.8 / python 2.5 - still the same latency. > >> > >> I am thinking that it may be related to SDL itself, and not the python > >> wrapper per se... I have seen some suggestions on lowering the chunk size > in > >> SDL. Does this map directly to the buffer size in pygame, or is there > some > >> magic happining behind the scenes? > >> > >> Thanks > >> > >> > >> > >> Wayne Koorts wrote: > >> > >> Does anyone have any suggestions on what I can try? > >> > >> Wouldn't hurt to upgrade to Pygame 1.8 for a start. > >> > >> Regards, > >> Wayne > >> > >> > >> > >
