src/songs/musicxmltosong.py

   1 """
   2 converstion d'un fichier musicxml en objet song minwii.
   3
   4 $Id$
   5 $URL$
   6 """
   7 import sys
   8 from types import StringTypes
   9 from xml.dom.minidom import parse
  10 from optparse import OptionParser
  11
  12 # Do4 <=> midi 60
  13 OCTAVE_REF = 4
  14 DIATO_SCALE = {'C' : 60,
  15                'D' : 62,
  16                'E' : 64,
  17                'F' : 65,
  18                'G' : 67,
  19                'A' : 69,
  20                'B' : 71}
  21 _marker = []
  22
  23
  24 class Note(object) :
  25     def __init__(self, node, divisions) :
  26         self.name = _getNodeValue(node, 'pitch/step')
  27         self.octave = int(_getNodeValue(node, 'pitch/octave'))
  28         self._duration = float(_getNodeValue(node, 'duration'))
  29         self.divisions = divisions
  30
  31     @property
  32     def midi(self) :
  33         mid = DIATO_SCALE[self.name]
  34         mid = mid + (self.octave - OCTAVE_REF) * 12
  35         return mid
  36
  37     @property
  38     def duration(self) :
  39         return self._duration / self.divisions
  40
  41
  42
  43 def _getNodeValue(node, path, default=_marker) :
  44     try :
  45         for name in path.split('/') :
  46             node = node.getElementsByTagName(name)[0]
  47         return node.firstChild.nodeValue
  48     except :
  49         if default is _marker :
  50             raise
  51         else :
  52             return default
  53
  54 def musicXml2Song(input, output) :
  55     if isinstance(input, StringTypes) :
  56         input = open(input, 'r')
  57
  58     d = parse(input)
  59     doc = d.documentElement
  60
  61     # TODO conversion préalable score-timewise -> score-partwise
  62     assert doc.nodeName == u'score-partwise'
  63
  64     parts = doc.getElementsByTagName('part')
  65     # on suppose que la première partie est le chant
  66     leadPart = parts[0]
  67
  68     # divisions de la noire
  69     divisions = 0
  70     for measureNode in leadPart.getElementsByTagName('measure') :
  71         divisions = int(_getNodeValue(measureNode, 'attributes/divisions', divisions))
  72         for noteNode in measureNode.getElementsByTagName('note') :
  73             note = Note(noteNode, divisions)
  74             print note.name, note.octave, note.midi, note.duration
  75
  76
  77 def main() :
  78     usage = "%prog musicXmlFile.xml outputSongFile.smwi [options]"
  79     op = OptionParser(usage)
  80
  81     options, args = op.parse_args()
  82     if len(args) != 2 :
  83         raise SystemExit(op.format_help())
  84
  85     musicXml2Song(*args)
  86
  87
  88
  89 if __name__ == '__main__' :
  90     sys.exit(main())