you are absolutely right. I can use very large buffers; however there are two things: I was using quite large ones (but not the immense ones you quoted) but say 8192 samples, and I was still getting dropouts. The larger the buffer the longer the dropouts were lasting for. Yes, I can try with larger buffers. But in any case, the target is not the MIDI app, that was just the test case, because it was simpler than hooking a keyboard and playing along.
Victor ----- Original Message ----- From: "Benjamin M. Schwartz" <[EMAIL PROTECTED]> To: "victor" <[EMAIL PROTECTED]> Cc: <[email protected]> Sent: Saturday, August 16, 2008 9:14 PM Subject: Re: comments on late joyrides re: rt performance > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > victor wrote: > ... > | Comparing the RT audio performance of the two, I must say > | I am disappointed with how worse it has got. > ... > | One of the things I have been playing with is a little MIDI file player > | (one of the test/example activities in > devel.laptop.org/activities/csndsugui), > | which uses a soundfont synthesis engine. > > While diminished RT performance is a serious problem, it occurs to me that > a properly designed MIDI file player should not require low latency at > all. The ALSA audio design makes it easy for applications to request long > buffers.. For example, the Distance activity plays audio with > > subprocess.call(["/usr/bin/aplay", "--buffer-time=10000000", fname]) > > to request a maximum-size buffer, precisely because of the latency issues > that I observed in testing. (Yes, this is incredibly ugly, but using > gstreamer in a multithreaded python app is uglier.) > > Interactive sound synthesis is a different matter, but for pure playback, > perhaps you just need a longer buffer. > > - --Ben > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v2.0.9 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org > > iEYEARECAAYFAkinNTgACgkQUJT6e6HFtqSoMACeJLmArHDWvm5v3ngHh8xII/4i > ShIAn2Oour0zr/4YkBE0CR4ubDiRLlXz > =PbFO > -----END PGP SIGNATURE----- _______________________________________________ Devel mailing list [email protected] http://lists.laptop.org/listinfo/devel
