1 # -*- coding: utf-8 -*-
2 """ utilities to convert midi note number to and from note names """
4 __all__ = ['note2midi', 'midi2note', 'freq2note']
7 py3 = sys.version_info[0] == 3
12 str_instances = (str, unicode)
13 int_instances = (int, long)
16 """Convert note name to midi note number.
18 Input string `note` should be composed of one note root
19 and one octave, with optionally one modifier in between.
21 List of valid components:
23 - note roots: `C`, `D`, `E`, `F`, `G`, `A`, `B`,
24 - modifiers: `b`, `#`, as well as unicode characters
25 `𝄫`, `♭`, `♮`, `♯` and `𝄪`,
26 - octave numbers: `-1` -> `11`.
36 corresponding midi note number
40 >>> aubio.note2midi('C#4')
42 >>> aubio.note2midi('B♭5')
48 If `note` was not a string.
50 If an error was found while converting `note`.
54 midi2note, freqtomidi, miditofreq
56 _valid_notenames = {'C': 0, 'D': 2, 'E': 4, 'F': 5, 'G': 7, 'A': 9, 'B': 11}
58 u'𝄫': -2, # double flat
59 u'♭': -1, 'b': -1, '\u266d': -1, # simple flat
60 u'♮': 0, '\u266e': 0, None: 0, # natural
61 '#': +1, u'♯': +1, '\u266f': +1, # sharp
62 u'𝄪': +2, # double sharp
64 _valid_octaves = range(-1, 10)
65 if not isinstance(note, str_instances):
66 raise TypeError("a string is required, got %s (%s)" % (note, str(type(note))))
67 if len(note) not in range(2, 5):
68 raise ValueError("string of 2 to 4 characters expected, got %d (%s)" \
70 notename, modifier, octave = [None]*3
73 notename, modifier, octave_sign, octave = note
74 octave = octave_sign + octave
76 notename, modifier, octave = note
78 octave = modifier + octave
81 notename, octave = note
83 notename = notename.upper()
86 if notename not in _valid_notenames:
87 raise ValueError("%s is not a valid note name" % notename)
88 if modifier not in _valid_modifiers:
89 raise ValueError("%s is not a valid modifier" % modifier)
90 if octave not in _valid_octaves:
91 raise ValueError("%s is not a valid octave" % octave)
93 midi = 12 + octave * 12 + _valid_notenames[notename] + _valid_modifiers[modifier]
95 raise ValueError("%s is outside of the range C-2 to G8" % note)
99 """Convert midi note number to note name.
104 input midi note number
113 >>> aubio.midi2note(70)
115 >>> aubio.midi2note(59)
121 If `midi` was not an integer.
123 If `midi` is out of the range `[0, 128]`.
127 note2midi, miditofreq, freqtomidi
129 if not isinstance(midi, int_instances):
130 raise TypeError("an integer is required, got %s" % midi)
131 if midi not in range(0, 128):
132 raise ValueError("an integer between 0 and 127 is excepted, got %d" % midi)
133 _valid_notenames = ['C', 'C#', 'D', 'D#', 'E', 'F', 'F#', 'G', 'G#', 'A', 'A#', 'B']
134 return _valid_notenames[midi % 12] + str(int(midi / 12) - 1)
137 """Convert frequency in Hz to nearest note name.
141 freq : float [0, 23000[
142 input frequency, in Hz
147 name of the nearest note
151 >>> aubio.freq2note(440)
153 >>> aubio.freq2note(220.1)
156 from aubio import freqtomidi
157 return midi2note(int(freqtomidi(freq)))