Source Code for Module jazzparser.taggers.chordmap

  1  """Chord type mappings 
  2   
  3  Chord supertaggers use mappings from the input chord vocabulary to a smaller  
  4  one. Various mappings are available and may be selected at model training  
  5  time. 
  6   
  7  """ 
  8  """ 
  9  ============================== License ======================================== 
 10   Copyright (C) 2008, 2010-12 University of Edinburgh, Mark Granroth-Wilding 
 11    
 12   This file is part of The Jazz Parser. 
 13    
 14   The Jazz Parser is free software: you can redistribute it and/or modify 
 15   it under the terms of the GNU General Public License as published by 
 16   the Free Software Foundation, either version 3 of the License, or 
 17   (at your option) any later version. 
 18    
 19   The Jazz Parser is distributed in the hope that it will be useful, 
 20   but WITHOUT ANY WARRANTY; without even the implied warranty of 
 21   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 22   GNU General Public License for more details. 
 23    
 24   You should have received a copy of the GNU General Public License 
 25   along with The Jazz Parser.  If not, see <http://www.gnu.org/licenses/>. 
 26   
 27  ============================ End license ====================================== 
 28   
 29  """ 
 30  __author__ = "Mark Granroth-Wilding <mark.granroth-wilding@ed.ac.uk>"  
 31   
 32  from jazzparser.utils.options import ModuleOption, choose_from_dict 
 33   
 34  NAMED_MAPPINGS = {} 
 35   
 36 -class NamedMapping(dict): 
 37      """ 
 38      Just a dictionary with a name. 
 39      """ 
 40 -    def __init__(self, name, *args, **kwargs): 
 41          dict.__init__(self, *args, **kwargs) 
 42          self.name = name 
 43   
 44  # Mapping to a small set of chord labels 
 45  SMALL_MAPPING = NamedMapping("small", { 
 46      ""     : "", 
 47      "m"    : "m",  
 48      "M7"   : "",  
 49      "o7"   : "o7", 
 50      "%7"   : "o7",  
 51      "aug"  : "aug", 
 52      "m,b5" : "o7", 
 53      "b5"   : "7", 
 54      "m,M7" : "m", 
 55      "7"    : "7", 
 56      "m7"   : "m7", 
 57      "aug7" : "aug", 
 58      "b5,7" : "7", 
 59      "sus4" : "", 
 60      "sus4,7" : "7", 
 61      "aug,M7" : "aug", 
 62      "b5,M7"  : "7", 
 63      "#5,m7"  : "m7", 
 64  }) 
 65   
 66  # Mapping to a larger set of chord labels 
 67  BIG_MAPPING = NamedMapping("big", { 
 68      ""     : "", 
 69      "m"    : "m",  
 70      "M7"   : "M7",  
 71      "o7"   : "o7", 
 72      "%7"   : "o7",  
 73      "aug"  : "aug", 
 74      "m,b5" : "o7", 
 75      "b5"   : "b5", 
 76      "m,M7" : "m", 
 77      "7"    : "7", 
 78      "m7"   : "m7", 
 79      "aug7" : "aug7", 
 80      "b5,7" : "7", 
 81      "sus4" : "sus4", 
 82      "sus4,7" : "sus4", 
 83      "aug,M7" : "aug", 
 84      "b5,M7"  : "7", 
 85      "#5,m7"  : "m7", 
 86  }) 
 87   
 88  # No mapping at all 
 89  IDENTITY_MAPPING = NamedMapping("none", { 
 90      ""     : "", 
 91      "m"    : "m",  
 92      "M7"   : "M7",  
 93      "o7"   : "o7", 
 94      "%7"   : "%7",  
 95      "aug"  : "aug", 
 96      "m,b5" : "m,b5", 
 97      "b5"   : "b5", 
 98      "m,M7" : "m,M7", 
 99      "7"    : "7", 
100      "m7"   : "m7", 
101      "aug7" : "aug7", 
102      "b5,7" : "b5,7", 
103      "sus4" : "sus4", 
104      "sus4,7" : "sus4,7", 
105      "aug,M7" : "aug,M7", 
106      "b5,M7"  : "b5,M7", 
107      "#5,m7"  : "#5,m7", 
108  }) 
109   
110  NAMED_MAPPINGS = dict([(mapping.name, mapping) for mapping in \ 
111      [ 
112          SMALL_MAPPING,  
113          IDENTITY_MAPPING,  
114          BIG_MAPPING, 
115      ] 
116  ]) 
117  MAPPINGS = NAMED_MAPPINGS.keys() 
118  DEFAULT_MAPPING = "small" 
119   
120 -def get_chord_mapping(name=None): 
121      """ 
122      Returns a dictionary chord type mapping identified by its name. 
123      A list of available mappings can be found in L{MAPPINGS}. 
124       
125      """ 
126      if name is None: 
127          name = DEFAULT_MAPPING 
128      return NAMED_MAPPINGS[name] 
129   
130 -def get_chord_mapping_module_option(name="chord_mapping"): 
131      return ModuleOption(name,  
132                          filter=choose_from_dict(NAMED_MAPPINGS), 
133                          help_text="Choose a mapping to apply to chord types "\ 
134                              "to reduce the chord vocabulary", 
135                          usage="%s=M, where M is one of %s. Default: %s" % \ 
136                              (name, ", ".join(MAPPINGS), DEFAULT_MAPPING), 
137                          default=get_chord_mapping()) 
138