Hi list,
First off, I'm new to pd but it seems to be a fantastic environment.
Big thanks to everyone who's worked on it.
I've run into a problem. I built a pd patch to translate joystick
button inputs into MIDI note signals using hid and noteout. Indeed
it functions correctly, and there are no logic errors that I can find
as far as which button triggers which note. However there is
noticeable latency, too much to use to play an instrument in realtime.
Using a MIDI keyboard to send the same notes (bypassing pd), I
encounter no latency that I am able to discern easily. I believe the
latency must be related to pd, either in my patch or in the hid
object, or in my joystick's USB interface (a playstation to USB
converter). Is this a known issue in pd or hid, or has anyone
encountered this before?
If it helps, I am running on a G4 Macintosh, using pd .38.4 extended,
and using the IAC Driver to get MIDI data between programs. I have
hid polling at 1ms intervals, and am using the Ableton Live demo as
my destination (triggering the Impulse plugin).
I am almost totally convinced that the latency is in the USB
interface, and therefore there is nothing I can do, but I figured it
was worth asking. I spent a while going through the list archives,
Google, and the documentation but did not find anything.
Thanks in advance!
Dave H.
USB HIDs are usually polled every 8ms to 10ms, which is plenty fast
(have you ever noticed the latency of your mouse pointer or
clicks?). I have not seen any reports of latency caused by [hid],
but I suppose it could be possible.
.hc
On Oct 7, 2007, at 8:30 PM, Warrior Bob wrote:
Hi list,
First off, I'm new to pd but it seems to be a fantastic environment. Big thanks to everyone who's worked on it.
I've run into a problem. I built a pd patch to translate joystick button inputs into MIDI note signals using hid and noteout. Indeed it functions correctly, and there are no logic errors that I can find as far as which button triggers which note. However there is noticeable latency, too much to use to play an instrument in realtime.
Using a MIDI keyboard to send the same notes (bypassing pd), I encounter no latency that I am able to discern easily. I believe the latency must be related to pd, either in my patch or in the hid object, or in my joystick's USB interface (a playstation to USB converter). Is this a known issue in pd or hid, or has anyone encountered this before?
If it helps, I am running on a G4 Macintosh, using pd .38.4 extended, and using the IAC Driver to get MIDI data between programs. I have hid polling at 1ms intervals, and am using the Ableton Live demo as my destination (triggering the Impulse plugin).
I am almost totally convinced that the latency is in the USB interface, and therefore there is nothing I can do, but I figured it was worth asking. I spent a while going through the list archives, Google, and the documentation but did not find anything.
Thanks in advance!
Dave H.
PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/ listinfo/pd-list
Computer science is no more related to the computer than astronomy is
related to the telescope. -Edsger Dykstra
-
Hans-Christoph Steiner -
Warrior Bob