Re: [ecasound] MIDI controller latency

New Message Reply Date view Thread view Subject view Author view Other groups

Subject: Re: [ecasound] MIDI controller latency
From: ben@slumber.dhs.org
Date: Mon Jan 22 2001 - 08:43:16 EET


I changed the value and recompiled. When the buffer size is 128 or
higher (down to about 80, actually) the delay is the same. Between
64 and about 80 there is no delay, but the buffer is too small for the
system to keep up with, which causes strange distortion (interesting,
but not what I had in mind.. :) ). There seems to be a fairly clear
cutoff point for the delay right about there, but it's hard to be sure.

Is there any other possible fix in sight, or should I just wait for
1.9.x? Is that code in progress yet?

Ben

> > I'm using ecasound v1.8.5d15 and a recent CVS version of ALSA (however,
> > I use ecasound with OSS emulation). When controlling effects parameters
> > with an external MIDI controller I get a large latency (about 1 second)
> [...]
> > problem with ALSA, because I can use the controller in realtime with
> > another program (SpiralSynth). What could be going on? Any help would
>
> This is very difficult indeed. First of all, ecasound's current
> MIDI-subsystem (module that does the actual reads from the MIDI-device)
> is not very good. It's ancient code that hasn't been modified much since -
> hmm - 1998-99 or so. And as I've said before, I intend to rewrite the
> whole thing during 1.9.x, so fixing the old code isn't a top priority.
>
> Anyway, even though the old code has its problems, there still
> shouldn't be the kind of delays you're experiencing. Have you tried to
> play around with the -b:bsize parameter (ie. also trying bigger
> values)? Another thing that comes to my mind is that your controller is
> outputting too much data and ecasound can't handle it. Just in case,
> you could try modifying the MIDI ring-buffer size in
> libecasound/eca-midi.h:
>
> - #define MIDI_IN_QUEUE_SIZE 1024
> + #define MIDI_IN_QUEUE_SIZE 16384

--
To unsubscribe send message 'unsubscribe' in the body of the
message to <ecasound-list-request@wakkanet.fi>.


New Message Reply Date view Thread view Subject view Author view Other groups

This archive was generated by hypermail 2b28 : Mon Jan 22 2001 - 09:04:57 EET