Re: How do I extract individual voices from chords

[Gilles THIBAULT]

Le dimanche 22 mars 2015, 00:54:08 Johan Vromans a écrit :
> On Sat, 21 Mar 2015 23:47:35 +0100
> 
> Kaj <address@hidden> wrote:
> > Or: How do I extract the first, second and third voice from the chord
> > score to use as input to the midi?
> 
> I once wrote a small tool (perl module) to split a polyphone MIDI into
> separate voices.
> 
> https://metacpan.org/pod/MIDI::Tweaks#MIDI::Track::split_hml
> 
> It may be helpful.
> 
> -- Johan
I have a solution in scheme but i use a function described here :
http://lsr.di.unimi.it/LSR/Item?id=761
So you have an \include file to download (see the following link).


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\version "2.18.2"
\include "chord.ly"
%% Download chord.ly here :
%% http://gillesth.free.fr/Lilypond/chord/

\layout {
  \override Score.RehearsalMark #'self-alignment-X = #LEFT
  \override Score.RehearsalMark #'Y-offset = #4
}

All = {
  <c' e' g'>8 <d' f' a'> <e' g'>
  <f' a'>
  g'8 a'<g' e' c'> <a' f' d'>
}

Soprano = { g'8 a' g' a' g' a' c' d' }
Alto = { e'8 f' g' a' g' a' e' f' }
Baritone = { c'8 d' e' f' g' a' g' a' }

% First score is to illustrate the chord version

\score {
  \new Staff {
    \mark "This is what I want..."
    \new Voice { \All  }
  }
  \layout {}
}

#(define (delete-doubled-notes music-with-chords)
(let ((chords (extract-named-music music-with-chords 'EventChord)))
   (for-each 
     (lambda(chord)
       (ly:music-set-property! chord 'elements 
         (delete-duplicates
          (ly:music-property chord 'elements)
          (lambda(note1 note2)
            (equal? (ly:music-property note1 'pitch)
                    (ly:music-property note2 'pitch))))))        
     chords)
   music-with-chords))
  
myScore = #(define-music-function (parser location musicA musicB musicC)
                                          (ly:music? ly:music? ly:music?)
(delete-doubled-notes
      (add-note musicC (add-note musicB musicA))))                              
           

% Second score illustrates the three voices separated

\score {
  \new Staff {
    \new Voice {
      \myScore \Soprano \Alto \Baritone
    }
  }
  \layout {}
}

%%%%%%%%%%%%%%%%%%%%%%%



-- 
Gilles

chord.png
Description: PNG image