Re: [Denemo-devel] midi input

[Richard Shann]

On Wed, 2008-11-05 at 08:27 -0600, Jeremiah Benham wrote:
> On Wed, 2008-11-05 at 08:13 +0000, Richard Shann wrote:
> > I have plugged in my m-audio keystation 49 and doing
> > cat /dev/midi
> > I can see the midi data coming in as I press the keys.
> 
> We can a universal function that responds to midi messages NOTE_ON,
> NOTE_OFF, PITCH_BEND, etc... and if jack is not available we can
> default
> to oss. Alsa does oss emulation so the user just has to provide the
> device path /dev/snd/midi02, /dev/midi or whatever. 
Is it alsa that is creating /dev/midi when I plug in the music-keyboard?
There is something responding to the hotplugging of my music-keyboard by
creating /dev/midi. I have both alsa and jack installed I think, but I
have no /dev/sequencer - I don't know what might create that (it would
have to be a soft synthesizer as I don't have dedicated hardware).
> 
> > It looks like for the non-jack branch we could possibly just collect
> the
> > simplest "noteon" data and use it as pitch input for Denemo. 
> 
> You are going to want to process it to determine if the input is
> overlapping or if the foot pedal has been pressed.  
Yes, but to achieve as much as the audio entry does we would just need
the noteon data. I think we should aim to model the midi in to look like
the keyboard in and the mouse in, so that we can make midi shortcuts
(like tweaking the pitch bend wheel to do a delete) using similar code.
I think it would be good to be able to do all the music entry from the
music-keyboard.
For example:
I can imagine setting up the music-keyboard for doing rhythm entry.
Perhaps whole note = C, half note D etc, then entering rhythms would
have the added advantage of audible feedback - you would soon get to
recognize if you had pressed a quarter note for a half note by the sound
it makes. Things like eighth-note sixteenth-note sixteenth-note would
make a little tune which you would recognise as you played it
(rhythmically) in on the music-keyboard.
Richard