Mercurial > hg > smallbox
view util/matlab_midi/piano_roll.m @ 224:fd0b5d36f6ad danieleb
Updated the contents of this branch with the contents of the default branch.
author | luisf <luis.figueira@eecs.qmul.ac.uk> |
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date | Thu, 12 Apr 2012 13:52:28 +0100 |
parents | a30e8bd6d948 |
children |
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function [PR,t,nn] = piano_roll(Notes,vel,ts) % % Inputs: % Notes: A 'notes' matrix as returned from midiInfo.m % vel: (optional) if vel==1, set value to note velocity instead of 1. (default 0) % ts: (optional) time step of one 'pixel' in seconds (default 0.01) % % Outputs: % PR: PR(ni,ti): value at note index ni, time index ti % t: t(ti): time value in seconds at time index ti % nn: nn(ni): note number at note index ti % % (i.e. t and nn provide 'real-world units' for PR) % % Copyright (c) 2009 Ken Schutte % more info at: http://www.kenschutte.com/midi if nargin < 2 vel = 0; end if nargin < 3 ts = 0.01; end Nnotes = size(Notes,1); n1 = round(Notes(:,5)/ts)+1; n2 = round(Notes(:,6)/ts)+1; if vel == 0 vals = ones(Nnotes,1); else vals = Notes(:,4); % velocity end for i=1:Nnotes PR(Notes(i,3), n1(i):n2(i)) = vals(i); end % create quantized time axis: t = linspace(0,max(Notes(:,6)),size(PR,2)); % note axis: nn = min(Notes(:,3)):max(Notes(:,3)); % truncate to notes used: PR = PR(nn,:);