ivan@81: function midi=matrix2midi(M,ticks_per_quarter_note,timesig)
ivan@81: % midi=matrix2midi(M,ticks_per_quarter_note)
ivan@81: %
ivan@81: % generates a midi matlab structure from a matrix
ivan@81: %  specifying a list of notes.  The structure output
ivan@81: %  can then be used by writemidi.m
ivan@81: %
ivan@81: % M: input matrix:
ivan@81: %   1     2    3  4   5  6  
ivan@81: %  [track chan nn vel t1 t2] (any more cols ignored...)
ivan@81: %
ivan@81: % optional arguments:
ivan@81: % - ticks_per_quarter_note: integer (default 300)
ivan@81: % - timesig: a vector of len 4 (default [4,2,24,8])
ivan@81: %
ivan@81: 
ivan@81: % Copyright (c) 2009 Ken Schutte
ivan@81: % more info at: http://www.kenschutte.com/midi
ivan@81: 
ivan@81: % TODO options:
ivan@81: %  - note-off vs vel=0
ivan@81: %  - tempo, ticks, etc
ivan@81: 
ivan@81: if nargin < 2
ivan@81:   ticks_per_quarter_note = 300;
ivan@81: end
ivan@81: 
ivan@81: if nargin < 3
ivan@81:   timesig = [4,2,24,8];
ivan@81: end
ivan@81: 
ivan@81: tracks = unique(M(:,1));
ivan@81: Ntracks = length(tracks);
ivan@81: 
ivan@81: % start building 'midi' struct
ivan@81: 
ivan@81: if (Ntracks==1)
ivan@81:   midi.format = 0;
ivan@81: else
ivan@81:   midi.format = 1;
ivan@81: end
ivan@81: 
ivan@81: midi.ticks_per_quarter_note = ticks_per_quarter_note;
ivan@81: 
ivan@81: tempo = 500000;   % could be set by user, etc...
ivan@81: % (microsec per quarter note)
ivan@81: 
ivan@81: for i=1:Ntracks
ivan@81:   
ivan@81:   trM = M(i==M(:,1),:);
ivan@81:   
ivan@81:   note_events_onoff = [];
ivan@81:   note_events_n = [];
ivan@81:   note_events_ticktime = [];
ivan@81:  
ivan@81:   % gather all the notes:
ivan@81:   for j=1:size(trM,1)
ivan@81:     % note on event:
ivan@81:     note_events_onoff(end+1)    = 1;
ivan@81:     note_events_n(end+1)        = j;
ivan@81:     note_events_ticktime(end+1) = 1e6 * trM(j,5) * ticks_per_quarter_note / tempo;
ivan@81:     
ivan@81:     % note off event:
ivan@81:     note_events_onoff(end+1)    = 0;
ivan@81:     note_events_n(end+1)        = j;
ivan@81:     note_events_ticktime(end+1) = 1e6 * trM(j,6) * ticks_per_quarter_note / tempo;
ivan@81:   end
ivan@81: 
ivan@81:   
ivan@81:   msgCtr = 1;
ivan@81:   
ivan@81:   % set tempo...
ivan@81:   midi.track(i).messages(msgCtr).deltatime = 0;
ivan@81:   midi.track(i).messages(msgCtr).type = 81;
ivan@81:   midi.track(i).messages(msgCtr).midimeta = 0;
ivan@81:   midi.track(i).messages(msgCtr).data = encode_int(tempo,3);
ivan@81:   midi.track(i).messages(msgCtr).chan = [];
ivan@81:   msgCtr = msgCtr + 1;
ivan@81:   
ivan@81:   % set time sig...
ivan@81:   midi.track(i).messages(msgCtr).deltatime = 0;
ivan@81:   midi.track(i).messages(msgCtr).type = 88;
ivan@81:   midi.track(i).messages(msgCtr).midimeta = 0;
ivan@81:   midi.track(i).messages(msgCtr).data = timesig(:);
ivan@81:   midi.track(i).messages(msgCtr).chan = [];
ivan@81:   msgCtr = msgCtr + 1;
ivan@81:   
ivan@81:   [junk,ord] = sort(note_events_ticktime);
ivan@81: 
ivan@81:   prevtick = 0;
ivan@81:   for j=1:length(ord)
ivan@81:     
ivan@81:     n = note_events_n(ord(j));
ivan@81:     cumticks = note_events_ticktime(ord(j));
ivan@81:     
ivan@81:     midi.track(i).messages(msgCtr).deltatime = cumticks - prevtick;
ivan@81:     midi.track(i).messages(msgCtr).midimeta = 1; 
ivan@81:     midi.track(i).messages(msgCtr).chan = trM(n,2);
ivan@81:     midi.track(i).messages(msgCtr).used_running_mode = 0;
ivan@81: 
ivan@81:     if (note_events_onoff(ord(j))==1)
ivan@81:       % note on:
ivan@81:       midi.track(i).messages(msgCtr).type = 144;
ivan@81:       midi.track(i).messages(msgCtr).data = [trM(n,3); trM(n,4)];
ivan@81:     else
ivan@81:       %-- note off msg:
ivan@81:       %midi.track(i).messages(msgCtr).type = 128;
ivan@81:       %midi.track(i).messages(msgCtr).data = [trM(n,3); trM(n,4)];
ivan@81:       %-- note on vel=0:
ivan@81:       midi.track(i).messages(msgCtr).type = 144;
ivan@81:       midi.track(i).messages(msgCtr).data = [trM(n,3); 0];
ivan@81:     end
ivan@81:     msgCtr = msgCtr + 1;
ivan@81:     
ivan@81:     prevtick = cumticks;
ivan@81:   end
ivan@81: 
ivan@81:   % end of track:
ivan@81:   midi.track(i).messages(msgCtr).deltatime = 0;
ivan@81:   midi.track(i).messages(msgCtr).type = 47;
ivan@81:   midi.track(i).messages(msgCtr).midimeta = 0;
ivan@81:   midi.track(i).messages(msgCtr).data = [];
ivan@81:   midi.track(i).messages(msgCtr).chan = [];
ivan@81:   msgCtr = msgCtr + 1;
ivan@81:   
ivan@81: end
ivan@81: 
ivan@81: 
ivan@81: % return a _column_ vector
ivan@81: % (copied from writemidi.m)
ivan@81: function A=encode_int(val,Nbytes)
ivan@81: 
ivan@81: A = zeros(Nbytes,1);  %ensure col vector (diff from writemidi.m...)
ivan@81: for i=1:Nbytes
ivan@81:   A(i) = bitand(bitshift(val, -8*(Nbytes-i)), 255);
ivan@81: end
ivan@81: