[sdiy] MIDI live interface project... suggestion

[Jason Proctor]

i realise you don't want to use a CPU, but another option would be 
using a Quicktime video with an embedded MIDI track. QT is generally 
very good about keeping its tracks in sync.

hth



At 9:04 PM -0500 12/16/09, Jean-Pierre Desrochers wrote:
>In fact that's what the MIDI interface is for.
>NTSC video lines have around 60usec each to store anything
>and the MIDI bits are 1/31250hz = 32usec wide each.
>So the idea is to grab all the incoming MIDI bits, store them
>in a large buffer and read them back to write them as 1's (100% peak 
>white level)
>and 0's (0% black level).
>One MIDI byte is 32usec X 10bits= 320usec wide.
>That represents around 320usec/63.5usec (one horiz. line width) = 5 
>horizontal lines time spent
>to receive one MIDI byte.
>So we could write each received MIDI byte in let's say every 6th horiz. line
>by putting 8 pulses on that line that represent the actual byte's 0's and 1's.
>Almost no delay involved between the MIDI in and video out.
>Any scenario possible here.
>JP
>
>
>
>On Wed 16/12/09 20:23 , Blake Griffith blake.benjamin.griffith at gmail.com sent:
>>  Very Interesting but I am confused as to how the midi data is stored on a
>>  video file.. ???
>>
>>  On Wed, Dec 16, 2009 at 10:55 AM, Jean-Pierre Desrochers wrote:
>>
>>  Hi list,
>>  This is a 'funky' project suggestion for anybody..
>>
>>  Some musicians use live MIDI controled devices
>>  (projectors, motors, visual effects, etc..)
>>  while playing some stuff at the same time
>>  on stage. These devices need some MIDI stream
>>  coming "normally" from a sequencer or a PC
>>  based MIDI software and a way to sync this all
>>  with the music on stage.. So we are talking
>>  about many instruments, sequencers, PC, etc..
>>  So what about a way to get rid of some stuff
>>  here and have a minimum of circuitry installed
>>  for live MIDI/music perfomance?
>>
>>  Here is the idea:
>>
>>  The project I think of is an interface
>>  that 'reads' an external MIDI stream (in studio)
>>  and... converts it to a NTSC video output
>>  that can be recorded using a video capture card.
>>  Obviously that capture card will at the same time
>>  record the music that needs to be in sync
>>  with the MIDI info..
>>  Now you have a 'video' that contains the MIDI information
>>  (I try to imagine the screen video that this would produce... !!)
>>  and the audio in a video file format, on a PC.
>>  You then burn a DVD with the saved video file.
>>  Finaly in a live performance,
>>  you play the DVD with a standard DVD player,
>>  connect the video out to the project interface to read back the
>>  MIDI stream out and at the same time play
>>  the musical audio tracks all sync together.. allways!
>>
>>  So on stage you only have this:
>>
>>  - DVD player
>>  - MIDI interface plugged to DVD player video out
>>  - Your normal audio mixing/amplifying stuff
>>  - All the normally used MIDI devices (projectors, etc..)
>>
>>  No more PC or sequencer stuff..
>>
>>  I'm sure I can forget something here
>>  but hey, this is just a suggestion on DIY list !
>>
>>  JP
>>
>>  _______________________________________________
>>  Synth-diy mailing list
>>  Synth-diy at dropmix.xs4all.nl
>>  http://dropmix.xs4all.nl/mailman/listinfo/synth-diy [1]
>>
>>
>>
>>  Links:
>>  ------
>>  [1] http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>
>>
>
>_______________________________________________
>Synth-diy mailing list
>Synth-diy at dropmix.xs4all.nl
>http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>
>
>
>_______________________________________________
>Synth-diy mailing list
>Synth-diy at dropmix.xs4all.nl
>http://dropmix.xs4all.nl/mailman/listinfo/synth-diy