Thread: [Qmidiarp-user] Feature Request: Export Functionality
Linux MIDI arpeggiator, phrase generator and controller LFO
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From: S C R. <rig...@gm...> - 2011-06-12 17:48:24
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Hello, I've been playing around with qmidiarp and it's really a fantastic tool. One problem I have right now is with jitter on my system. I primarily use qmidiarp for recording, and one way for me to workaround the jitter might be to have an export function so that I could dump to a mid file and import into another sequencer. Is this a doable request? --Steve |
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From: Sascha S. <ung...@gm...> - 2011-06-12 18:28:31
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Hi, I think the problem will be that you will have to define which notes should be exported. If you use an arpeggiator the notes you press on the keyboard make the sound, so you must record the notes generated and this only makes sense with another sequencer. If you only use the sequencer, setting the right quantisation in the DAW might help Maybe I am wrong ... greetings from belgium, Sascha 2011/6/12 S C Rigler <rig...@gm...>: > Hello, > > I've been playing around with qmidiarp and it's really a fantastic > tool. One problem I have right now is with jitter on my system. I > primarily use qmidiarp for recording, and one way for me to workaround > the jitter might be to have an export function so that I could dump to > a mid file and import into another sequencer. Is this a doable > request? > > --Steve > > ------------------------------------------------------------------------------ > EditLive Enterprise is the world's most technically advanced content > authoring tool. Experience the power of Track Changes, Inline Image > Editing and ensure content is compliant with Accessibility Checking. > http://p.sf.net/sfu/ephox-dev2dev > _______________________________________________ > Qmidiarp-user mailing list > Qmi...@li... > https://lists.sourceforge.net/lists/listinfo/qmidiarp-user > |
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From: Frank K. <goe...@ya...> - 2011-06-12 18:37:33
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Hi Steve, ----- Mail original ----- > De : S C Rigler <rig...@gm...> > À : qmi...@li... > Cc : > Envoyé le : Dimanche 12 Juin 2011 19h47 > Objet : [Qmidiarp-user] Feature Request: Export Functionality > > Hello, > > I've been playing around with qmidiarp and it's really a fantastic > tool. One problem I have right now is with jitter on my system. I > primarily use qmidiarp for recording, and one way for me to workaround > the jitter might be to have an export function so that I could dump to > a mid file and import into another sequencer. Is this a doable > request? > > --Steve > Any attempts made to reduce your jitter? Do you have this with ALSA in general? Then a kernel with 1000Hz timer might arrange things. If the jitter happens with JACK MIDI Sync, maybe a reduced latency can improve the situation. How would you export the MIDI data? With a tool like QMidiArp, mainly done for live play/editing it would need an inbuilt recording tool. Is this what you have in mind? Otherwise, exporting the sequences and LFO data as MIDI files should not be a problem but you could do this with other tools as well. Have you tried recording QMidiArp's output into Qtractor for instance? Regards Frank |
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From: S C R. <rig...@gm...> - 2011-06-13 00:03:48
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On Sun, Jun 12, 2011 at 1:37 PM, Frank Kober <goe...@ya...> wrote: > Hi Steve, > > > Any attempts made to reduce your jitter? Do you have this with ALSA in general? > Then a kernel with 1000Hz timer might arrange things. If the jitter happens with > JACK MIDI Sync, maybe a reduced latency can improve the situation. > > How would you export the MIDI data? With a tool like QMidiArp, mainly done for > live play/editing it would need an inbuilt recording tool. Is this what you have in mind? > Otherwise, exporting the sequences and LFO data as MIDI files should not be a > problem but you could do this with other tools as well. > Have you tried recording QMidiArp's output into Qtractor for instance? > > Regards > Frank > I've tried to reduce the jitter as much as I can. I'm running 2.6.39 right and it was built doing "make oldconfig" against the config from a Planet CCRMA RT kernel so it has a 1000HZ timer. What I was hoping for was something where the sequences and LFO data could be exported as midi files. I've been experimenting a bit and it seems that this is mainly a problem when the system is under load. When I record QMidiArp into Qtractor it lags a little bit, but not so much that quantizing doesn't put things back into time. However, when QTractor is also sequencing an instance of Yoshimi things start to lag quite a bit more and get inconsistent enough that quantizing will help, but it needs quite a bit of manual cleanup afterward. If QMidiArp is sequencing the Yoshimi instance and simultaneously recording into Qtractor then it gets so inconsistent that quantizing just makes things worse. The weird thing is once I play back the sequence from Qtractor and the system is under load I don't hear any noticeable jitter. But anyways, I think I have a workaround for now. Thanks, Steve |
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From: Frank K. <goe...@ya...> - 2011-06-13 09:14:41
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----- Mail original ----- > De : S C Rigler <rig...@gm...> > À : Frank Kober <goe...@ya...> > Cc : "qmi...@li..." <qmi...@li...> > Envoyé le : Lundi 13 Juin 2011 1h55 > Objet : Re: Re : [Qmidiarp-user] Feature Request: Export Functionality > The > weird thing is once I play back the sequence from Qtractor and the > system is under load I don't hear any noticeable jitter. > That is interesting indeed. Since Qtractor lets you choose different timers, do you use a timer different from the first entry in Qtractor's timer choice for the ALSA queue? And secondly, does seq24 also give no jitter in your case? There might be something to fix... Frank |
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From: Frank K. <goe...@ya...> - 2011-06-13 12:06:07
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----- Mail original ----- > De : S C Rigler <rig...@gm...> > À : Frank Kober <goe...@ya...> > Cc : "qmi...@li..." <qmi...@li...> > Envoyé le : Lundi 13 Juin 2011 1h55 > Objet : Re: Re : [Qmidiarp-user] Feature Request: Export Functionality Another question that came to my mind: Which qmidiarp version are you using? If it is 0.4.1 be sure to have the patch applied before building Cheers |
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From: S C R. <rig...@gm...> - 2011-06-14 00:27:27
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On Mon, Jun 13, 2011 at 4:57 AM, Frank Kober <goe...@ya...> wrote: > > > ----- Mail original ----- >> De : S C Rigler <rig...@gm...> >> À : Frank Kober <goe...@ya...> >> Cc : "qmi...@li..." <qmi...@li...> >> Envoyé le : Lundi 13 Juin 2011 1h55 >> Objet : Re: Re : [Qmidiarp-user] Feature Request: Export Functionality > > > > Another question that came to my mind: Which qmidiarp version are you using? > If it is 0.4.1 be sure to have the patch applied before building > Cheers > Yes, this is 0.4.1 with the patch applied. Originally I had Qtractor using set to "default" for the queue timer, but I've since it changed it to "System Timer (1000HZ)"...probably the same thing. I uploaded a couple of examples to my dropbox. They are all using Qtractor as the transport master and at 115BPM recorded into MixBus with Hydrogen doing a click: The original "source arp" with QMidiArp sequencing Yoshimi: http://dl.dropbox.com/u/9838571/qmidiarp_arp.mp3 The first 4 bars of the "source arp" cleaned up and looped 4 times in Qtractor sequencing Yoshimi: http://dl.dropbox.com/u/9838571/qtractor_arp.mp3 The same 4 bars as before, this time with seq24 sequencing Yoshimi: http://dl.dropbox.com/u/9838571/seq24_arp.mp3 Thanks, Steve |
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From: Frank K. <goe...@ya...> - 2011-06-14 18:38:46
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> Yes, this is 0.4.1 with the patch applied. Originally I had Qtractor > using set to "default" for the queue timer, but I've since it > changed > it to "System Timer (1000HZ)"...probably the same thing. > > I uploaded a couple of examples to my dropbox. They are all using > Qtractor as the transport master and at 115BPM recorded into MixBus > with Hydrogen doing a click: > Thanks Steve, the examples clearly show the problem, however more questions before digging into what this could be (I clearly don't reproduce it here on an old 2.6.33 rt kernel): 1) Does the jitter appear as well when not using jack transport sync? No proof needed if your impression is so. 2) What is your JACK latency ? 3) Do you use a CPU frequency governor like ondemand that might vary CPU frequency during play? Reasons for my questions are, I'd like to know whether qmidiarp just poorly syncs due to some reason or whether the ALSA timer for some reason is unstable Thanks in advance Frank |
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From: S C R. <rig...@gm...> - 2011-06-15 12:34:03
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On Tue, Jun 14, 2011 at 1:38 PM, Frank Kober <goe...@ya...> wrote: > Thanks Steve, > the examples clearly show the problem, however more questions before digging into what this could be (I clearly don't reproduce it here on an old 2.6.33 rt kernel): > 1) Does the jitter appear as well when not using jack transport sync? No proof needed if your impression is so. > 2) What is your JACK latency ? > 3) Do you use a CPU frequency governor like ondemand that might vary CPU frequency during play? > > Reasons for my questions are, I'd like to know whether qmidiarp just poorly syncs due to some reason or whether the ALSA timer for some reason is unstable > > Thanks in advance > Frank > I experimented with it a bit more and I can't for sure say if there is a difference between using jack transport sync and the internal timer. It sounds like it's in time without jack transport sync, but to compare, I tried using jack transport sync with no accompaniment and it sounded fine there as well. So it seems that it's just when there are other parts playing that it sounds like it's not in time. But anyways, to answer your other questions: I went back to a rt patch 2.6.33 kernel to record the examples. Just FYI, my laptop isn't completely supported until 2.6.35 and one of the workarounds I need to keep it from locking up on older kernels is to boot with "nohpet". The behavior is the same, though, between 2.6.39 and 2.6.33-rt. According to Qjackctl, the latency is 2.9ms (64 frames/period, 2 periods/buffer). The CPU frequency governor is configured for "performance". --Steve |
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From: Frank K. <goe...@ya...> - 2011-06-15 21:43:30
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----- Mail original ----- > De : S C Rigler <rig...@gm...> > À : Frank Kober <goe...@ya...> > Cc : ""qmi...@li..."" <qmi...@li...> > Envoyé le : Mercredi 15 Juin 2011 14h33 > Objet : Re: Re : Re : Re : [Qmidiarp-user] Feature Request: Export Functionality [...Timing issues...] I remembered this LAU thread about timing in ALSA seq, and particularly one info from Pedro might be useful to find out more about timers used in ALSA seq. Maybe the timers used by different seq queues differ on your system? ----------------------------LAU Message------------------------------ Re: Is ALSA using hrtimer? by Pedro Lopez-Cabanillas :: Rate this Message: | View Threaded | Show Only this Message On Thursday, May 27, 2010, Grant wrote: > I have hrtimer support compiled into my kernel, but when I watch 'top' > while music is playing I can see that 'timer' uses CPU cycles but > 'hrtimer' never does. How can I find out if ALSA is using hrtimer? > > - Grant In addition to Clemens' message, ALSA MIDI sequencer can use several timer sources. To see which ALSA timers are available, use a command like this: $ cat /proc/asound/timers When a program is using the ALSA MIDI sequencer, you can query the timers assigned to each queue using another command: $ cat /proc/asound/seq/timer Alternatively, the utility "drumstick-sysinfo" [1] shows this information using a friendly format. Regards, Pedro |
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From: Frank K. <goe...@ya...> - 2011-06-15 21:01:22
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----- Mail original ----- > De : S C Rigler <rig...@gm...> > À : Frank Kober <goe...@ya...> > Cc : ""qmi...@li..."" <qmi...@li...> > Envoyé le : Mercredi 15 Juin 2011 14h33 > Objet : Re: Re : Re : Re : [Qmidiarp-user] Feature Request: Export Functionality > > On Tue, Jun 14, 2011 at 1:38 PM, Frank Kober <goe...@ya...> wrote: >> Thanks Steve, >> the examples clearly show the problem, however more questions before > digging into what this could be (I clearly don't reproduce it here on an old > 2.6.33 rt kernel): >> 1) Does the jitter appear as well when not using jack transport sync? No > proof needed if your impression is so. >> 2) What is your JACK latency ? >> 3) Do you use a CPU frequency governor like ondemand that might vary CPU > frequency during play? >> >> Reasons for my questions are, I'd like to know whether qmidiarp just > poorly syncs due to some reason or whether the ALSA timer for some reason is > unstable >> >> Thanks in advance >> Frank >> > > I experimented with it a bit more and I can't for sure say if there is > a difference between using jack transport sync and the internal timer. > It sounds like it's in time without jack transport sync, but to > compare, I tried using jack transport sync with no accompaniment and > it sounded fine there as well. So it seems that it's just when there > are other parts playing that it sounds like it's not in time. > > But anyways, to answer your other questions: I went back to a rt patch > 2.6.33 kernel to record the examples. Just FYI, my laptop isn't > completely supported until 2.6.35 and one of the workarounds I need to > keep it from locking up on older kernels is to boot with "nohpet". > The behavior is the same, though, between 2.6.39 and 2.6.33-rt. > > According to Qjackctl, the latency is 2.9ms (64 frames/period, 2 > periods/buffer). The CPU frequency governor is configured for > "performance". > > --Steve OK thanks again Steve, that rules out some suspects. I'll have to have a closer look, I beleive one other person has had similar problems, and they seem to be appearing only on some systems, and, strangely not with other alsa sequencers, so a fix must exist in some way. For the time being I can only recommend checking out the latest git version that has one transport start fix that appeared only when seq24 was in the jack transport group, probably won't fix your issue though. I'll let you know if there is a fix in sight Others, please report if you have similar timing jitter issues. Frank |
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From: S C R. <rig...@gm...> - 2011-06-24 16:42:22
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On Wed, Jun 15, 2011 at 4:01 PM, Frank Kober <goe...@ya...> wrote: > OK thanks again Steve, that rules out some suspects. I'll have to have a closer look, > I beleive one other person has had similar problems, and they seem to > be appearing only on some systems, and, strangely not with other alsa sequencers, > so a fix must exist in some way. > For the time being I can only recommend checking out the latest git version that > has one transport start fix that appeared only when seq24 was in the jack transport > group, probably won't fix your issue though. > I'll let you know if there is a fix in sight > > Others, please report if you have similar timing jitter issues. > > > Frank > Probably a dumb question, but how to check out the git version? --Steve |
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From: Frank K. <goe...@ya...> - 2011-06-24 18:03:31
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> Probably a dumb question, but how to check out the git version? > No dumb question git clone git://qmidiarp.git.sourceforge.net/gitroot/qmidiarp/qmidiarp cd qmidiarp autoreconf -i ./configure make sudo make install ---- Frank |
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