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I would lean towards trigger "events" as well, but I'd probably want some

input from DAW developers before I just wrote an extension myself.
Jeremy
On Tue, Dec 28, 2010 at 3:00 PM, Paul Giblock  wrote:
> It sounds to me like the generic "Beat" Event would be a "TriggerEvent".

quoted text
> Triggers could be for clock, gates, envelopes, etc..  At least I think this

> would model the way old modulars would interact fairly well.  But: Is it

> modeled as an audio-port with peaks to denote the triggers, or as an event

> port with timed events?  I'm leaning towards events personally.

>

> -Paul

>

>

> On Tue, Dec 28, 2010 at 2:29 PM, JohnLM  wrote:

>

>> Well I think the idea is quite good! I could think of few more uses,

>> including real-time DJ "crossfade/mix" sync by beats, and such.

>>

>> I haven't looked into LV2 much yet, but one thing is sure. You can't

>> make the plugin universal. Any host dealing with such plugin must be

>> aware of it's purpose whether the output is simply audio clicks or some

>> kind of event interface.

>>

>> As much as I understand LV2 does not mandate universal-use "filter"

>> plugins as LADSPA did, so you're good with extending it as you see fit.

>> Host code modifications will be required, but if you make it generic

>> enough, the interface could be picked up by various projects.

>>

>>

>> On Sun, 26 Dec 2010 01:58:13 -0500

>> Jeremy  wrote:

>>

>> > Hi all,

>> >

>> > So I'm writing some LV2 plugins to wrap up the Aubio audio analysis

>> > library,

>> > and I'm not sure exactly how to handle functions like "onset"

>> > detection. Currently, it just outputs clicks to an audio port (0 when

>> > no beat, 1 when beat is detected).  However, this doesn't take

>> > advantage of the power of LV2.  It is unclear to hosts and other

>> > plugins exactly what sort of data is coming out.

>> >

>> > I was thinking that maybe it would output MIDI, as midi matches the

>> > "event based" aspect of beat detection.  Perhaps sending out MIDI

>> > beat clock signals ?

>> > However, that doesn't really match the sort of data that the Aubio

>> > functions detect. Maybe it could just send a midi note on event?

>> >

>> > It seems like maybe some sort of LV2 specific extension might be in

>> > order? The Event Port

>> > extension seems to define everything I need: sending timestamped

>> > events with no extra information attached.  The question is: does it

>> > require some sort of further extension to define what a beat port is

>> > in the way the MidiEvent extension does?

>> >

>> > Of course, this raises the question: Is a port specific for "beats"

>> > even necessary?  I can think of a few cases:

>> >

>> >    - DAW uses beat signals to set up markers on a track

>> >    - DAW uses beat signals to break a percussive track up into beats.

>> >    - Delay effect uses beat signals to have a timed delay

>> >    - Automatic drummer adds on a percussion part to audio with

>> > varying tempo

>> >    - ? other beat-synchronous effects?

>> >

>> > Anyway, I'm wondering what you all think would be the best option, or

>> > whether you think functionality like this is even warranted in an LV2

>> > plugin (should analysis plugins stick to VAMP?).  So let me know what

>> > you think.

>> >

>> > Jeremy Salwen

>>

>> _______________________________________________

>> Linux-audio-dev mailing list

>> Linux-audio-dev@lists.linuxaudio.org

>> http://lists.linuxaudio.org/listinfo/linux-audio-dev

>>

>

>

> _______________________________________________

> Linux-audio-dev mailing list

> Linux-audio-dev@lists.linuxaudio.org

> http://lists.linuxaudio.org/listinfo/linux-audio-dev

>

>

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Content-Transfer-Encoding: quoted-printable
I would lean towards trigger "events" as well, but I'd probab=

ly want some input from DAW developers before I just wrote an extension mys=

elf.JeremyOn Tue, Dec 28, 2010 a=

t 3:00 PM, Paul Giblock <pgiblox@gmail.com> wrote:
It sounds to me l=

ike the generic "Beat" Event would be a "TriggerEvent".=

 Triggers could be for clock, gates, envelopes, etc..=A0 At least I think t=

his would model the way old modulars would interact fairly well.=A0 But: Is=

 it modeled as an audio-port with peaks to denote the triggers, or as an ev=

ent port with timed events?=A0 I'm leaning towards events personally.
-PaulOn Tue, Dec 28, 2010 at 2:29 PM, JohnLM <johnlm@apollo.lv>=

 wrote:
Well I think the idea is quite good! I could think of few more uses,

including real-time DJ "crossfade/mix" sync by beats, and such.
I haven't looked into LV2 much yet, but one thing is sure. You can'=

t

make the plugin universal. Any host dealing with such plugin must be

aware of it's purpose whether the output is simply audio clicks or some=
kind of event interface.
As much as I understand LV2 does not mandate universal-use "filter&quo=

t;

plugins as LADSPA did, so you're good with extending it as you see fit.=
Host code modifications will be required, but if you make it generic

enough, the interface could be picked up by various projects.
On Sun, 26 Dec 2010 01:58:13 -0500

Jeremy <jeremy=

bubs@gmail.com> wrote:
> Hi all,

quoted text
>

> So I'm writing some LV2 plugins to wrap up the Aubio audio analysi=

s

quoted text
> library<http:=

//aubio.org/>,

quoted text
> and I'm not sure exactly how to handle functions like "o=

nset"

quoted text
> detection. Currently, it just outputs clicks to an audio port (0 when<=

br>

quoted text
> no beat, 1 when beat is detected). =A0However, this doesn't take

> advantage of the power of LV2. =A0It is unclear to hosts and other

> plugins exactly what sort of data is coming out.

>

> I was thinking that maybe it would output MIDI, as midi matches the

> "event based" aspect of beat detection. =A0Perhaps sending o=

ut MIDI

quoted text
> beat clock signals <http://en.wikipedia.org/wiki/MIDI_beat_cl=

ock>?

quoted text
> However, that doesn't really match the sort of data that the =

Aubio

quoted text
> functions detect. Maybe it could just send a midi note on event?

>

> It seems like maybe some sort of LV2 specific extension might be in

> order? The Event Port <http://lv2plug.in/ns/ext/event/#EventPort=

>

quoted text
> extension seems to define everything I need: sending timestamped<=

br>

quoted text
> events with no extra information attached. =A0The question is: does it=

> require some sort of further extension to define what a beat port is

quoted text
> in the way the MidiEvent extension does?

>

> Of course, this raises the question: Is a port specific for "beat=

s"

quoted text
> even necessary? =A0I can think of a few cases:

>

> =A0 =A0- DAW uses beat signals to set up markers on a track

> =A0 =A0- DAW uses beat signals to break a percussive track up into bea=

ts.

quoted text
> =A0 =A0- Delay effect uses beat signals to have a timed delay

> =A0 =A0- Automatic drummer adds on a percussion part to audio with

> varying tempo

> =A0 =A0- ? other beat-synchronous effects?

>

> Anyway, I'm wondering what you all think would be the best option,=

 or

quoted text
> whether you think functionality like this is even warranted in an LV2<=

br>

quoted text
> plugin (should analysis plugins stick to VAMP?). =A0So let me know wha=

t

quoted text
> you think.

>

> Jeremy Salwen

_______________________________________________<=

br>

Linux-audio-dev mailing list

L=

inux-audio-dev@lists.linuxaudio.org

http://lists.linuxaudio.org/listinfo/linux-audio-dev
_______________________________________________

Linux-audio-dev mailing list

Linux-audio-dev@lis=

ts.linuxaudio.org

http://lists.linuxaudio.org/listinfo/linux-audio-dev
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