def analyze_7th_chord(chord):
"""
:param chord:
:return: chord_notes, chord_type_full, chord_modes
Example:
>>> chord_notes, chord_type_full, results = analyze_chord("G7")
>>> for chord_degree, key, harmonic_func_full in results:
... print("{} (comprising {}) is a {} chord ({}) of the key of {}".format(chord_type_full,', '.join(chord_notes),
... chord_degree, harmonic_func_full,
... key))
G dominant seventh (comprising G, B, D, F) is a V chord (dominant seventh) of the key of C
"""
chord_notes = chords.from_shorthand(chord)
chord_type_full = chords.determine_seventh(chord_notes)[0]
chord_type_short = chords.determine_seventh(chord_notes, shorthand=True)[0]
type_key = (
"M7"
if chord_type_short[-2:] == "M7"
else ("m7" if chord_type_short[-2:] == "m7" else ("m7b5" if chord_type_short[-2:] == "m7b5" else "7"))
)
chord_modes = []
for key in CIRCLE_OF_5THS:
harmonic_func = determine(chord_notes, key, shorthand=True)[0]
harmonic_func_full = determine(chord_notes, key, shorthand=False)[0]
chord_degree = harmonic_func[:-1]
if chord_degree in MODE_CHORD_TYPE:
func_chord_type = MODE_CHORD_TYPE[chord_degree]
if func_chord_type == type_key:
chord_modes.append((chord_degree, key, harmonic_func_full))
return chord_notes, chord_type_full, chord_modes
def test_determine(self):
self.assertEqual(["tonic"], progressions.determine(["C", "E", "G"],
"C"))
self.assertEqual(["tonic seventh"],
progressions.determine(["C", "E", "G", "B"], "C"))
self.assertEqual(
["tonic dominant seventh"],
progressions.determine(["C", "E", "G", "Bb"], "C"),
)
self.assertEqual(["I"],
progressions.determine(["C", "E", "G"], "C", True))
self.assertEqual(["I"],
progressions.determine(["E", "G", "C"], "C", True))
self.assertEqual(["I"],
progressions.determine(["G", "C", "E"], "C", True))
self.assertEqual(["V7"],
progressions.determine(["G", "B", "D", "F"], "C",
True))
self.assertEqual(["Vm7", "bviiM6"],
progressions.determine(["G", "Bb", "D", "F"], "C",
True))
self.assertEqual(
[["I"], ["V"]],
progressions.determine([["C", "E", "G"], ["G", "B", "D"]], "C",
True),
)
self.assertEqual(["bii", "bIVM6"],
progressions.determine(["Db", "Fb", "Ab"], "C", True))
def analyze_7th_chord(chord):
"""
:param chord:
:return: chord_notes, chord_type_full, chord_modes
Example:
>>> chord_notes, chord_type_full, results = analyze_chord("G7")
>>> for chord_degree, key, harmonic_func_full in results:
... print("{} (comprising {}) is a {} chord ({}) of the key of {}".format(chord_type_full,', '.join(chord_notes),
... chord_degree, harmonic_func_full,
... key))
G dominant seventh (comprising G, B, D, F) is a V chord (dominant seventh) of the key of C
"""
chord_notes = chords.from_shorthand(chord)
chord_type_full = chords.determine_seventh(chord_notes)[0]
chord_type_short = chords.determine_seventh(chord_notes, shorthand=True)[0]
type_key = 'M7' if chord_type_short[-2:] == 'M7' else (
'm7' if chord_type_short[-2:] == 'm7' else
('m7b5' if chord_type_short[-2:] == 'm7b5' else '7'))
chord_modes = []
for key in CIRCLE_OF_5THS:
harmonic_func = determine(chord_notes, key, shorthand=True)[0]
harmonic_func_full = determine(chord_notes, key, shorthand=False)[0]
chord_degree = harmonic_func[:-1]
if chord_degree in MODE_CHORD_TYPE:
func_chord_type = MODE_CHORD_TYPE[chord_degree]
if func_chord_type == type_key:
chord_modes.append((chord_degree, key, harmonic_func_full))
return chord_notes, chord_type_full, chord_modes
def test_determine(self): self.assertEqual(['tonic'], progressions.determine(["C", "E", "G"], 'C')) self.assertEqual(['tonic seventh'], progressions.determine(["C", "E", "G", "B"], 'C')) self.assertEqual(['tonic dominant seventh'], progressions.determine(["C", "E", "G", "Bb"], 'C')) self.assertEqual(['I'], progressions.determine(["C", "E", "G"], 'C', True)) self.assertEqual(['I'], progressions.determine(["E", "G", "C"], 'C', True)) self.assertEqual(['I'], progressions.determine(["G", "C", "E"], 'C', True)) self.assertEqual(['V7'], progressions.determine(["G", "B", "D", "F"], 'C', True)) self.assertEqual(['Vm7', 'bviiM6'], progressions.determine(["G", "Bb", "D", "F"], 'C', True)) self.assertEqual([['I'], ['V']], progressions.determine([["C", "E", "G"], ["G", "B", "D"]], "C", True)) self.assertEqual(['bii', 'bIVM6'], progressions.determine(["Db", "Fb", "Ab"], 'C', True))
def determine_progression(self, shorthand=False):
"""Return a list of lists [place_in_beat, possible_progressions]."""
res = []
for x in self.bar:
res.append([x[0], progressions.determine(x[2].get_note_names(),
self.key.key, shorthand)])
return res
def determine_progression(self, shorthand=False):
"""Return a list of lists [place_in_beat, possible_progressions]."""
res = []
for x in self.bar:
res.append([x[0], progressions.determine(x[2].get_note_names(),
self.key.key, shorthand)])
return res
def test_determine(self):
self.assertEqual(['tonic'], progressions.determine(['C', 'E', 'G'], 'C'
))
self.assertEqual(['tonic seventh'], progressions.determine(['C', 'E',
'G', 'B'], 'C'))
self.assertEqual(['tonic dominant seventh'], progressions.determine(['C'
, 'E', 'G', 'Bb'], 'C'))
self.assertEqual(['I'], progressions.determine(['C', 'E', 'G'], 'C',
True))
self.assertEqual(['I'], progressions.determine(['E', 'G', 'C'], 'C',
True))
self.assertEqual(['I'], progressions.determine(['G', 'C', 'E'], 'C',
True))
self.assertEqual(['V7'], progressions.determine(['G', 'B', 'D', 'F'],
'C', True))
self.assertEqual(['Vm7', 'bviiM6'], progressions.determine(['G', 'Bb',
'D', 'F'], 'C', True))
self.assertEqual([['I'], ['V']], progressions.determine([['C', 'E', 'G'
], ['G', 'B', 'D']], 'C', True))
self.assertEqual(['bii', 'bIVM6'], progressions.determine(['Db', 'Fb',
'Ab'], 'C', True))
def test_determine(self):
self.assertEqual(['tonic'], progressions.determine(['C', 'E', 'G'],
'C'))
self.assertEqual(['tonic seventh'],
progressions.determine(['C', 'E', 'G', 'B'], 'C'))
self.assertEqual(['tonic dominant seventh'],
progressions.determine(['C', 'E', 'G', 'Bb'], 'C'))
self.assertEqual(['I'],
progressions.determine(['C', 'E', 'G'], 'C', True))
self.assertEqual(['I'],
progressions.determine(['E', 'G', 'C'], 'C', True))
self.assertEqual(['I'],
progressions.determine(['G', 'C', 'E'], 'C', True))
self.assertEqual(['V7'],
progressions.determine(['G', 'B', 'D', 'F'], 'C',
True))
self.assertEqual(['Vm7', 'bviiM6'],
progressions.determine(['G', 'Bb', 'D', 'F'], 'C',
True))
self.assertEqual([['I'], ['V']],
progressions.determine(
[['C', 'E', 'G'], ['G', 'B', 'D']], 'C', True))
self.assertEqual(['bii', 'bIVM6'],
progressions.determine(['Db', 'Fb', 'Ab'], 'C', True))
def get_chord(prev_chord=None, key='A'):
if prev_chord is None:
return chords.tonic(key)
hfunc = progressions.determine(prev_chord, key, True)[0]
if hfunc == 'I':
return choice([
chords.ii(key),
chords.iii(key),
chords.IV(key),
chords.IV7(key),
chords.V(key),
chords.V7(key)
])
elif hfunc == 'ii':
return choice([chords.iii(key), chords.V(key)])
elif hfunc == 'iii':
return choice(
[chords.ii(key),
chords.IV(key),
chords.IV7(key),
chords.vi(key)])
elif hfunc == 'IV':
return choice([
chords.I(key),
chords.ii(key),
chords.iii(key),
chords.V(key),
chords.V7(key)
])
elif hfunc == 'V':
return choice([chords.I(key), chords.vi(key)])
elif hfunc == 'vi':
return choice([chords.ii(key), chords.IV(key)])
else:
return chords.I(key)
def gen_numerals(soup):
# create prog_numerals list by passing longhand_chords, key & True (asks for numerals) to progressions.determine
prog_numerals = progressions.determine(longhand_trans(soup), key(soup), True)
return prog_numerals
exit()
# python music.py --chord-progression "1,2,4,5" --key C
elif args.chord_progression:
key, scale, chord_progression = expand_progression(
args.chord_progression)
elif args.repeat_progression:
key, scale, chord_progression = load_chord_progression(
"song", key=args.key, scale=args.scale)
else:
key, scale, chord_progression = generate_progression(key=args.key,
scale=args.scale,
minor=args.minor)
chord_chart = [chord_symbol(chord) for chord in chord_progression]
roman_chords = [
progressions.determine(chord, key, True)[0]
for chord in chord_progression
]
pad = Waitstaff.choose_from_group("Pad")
instrument = find_instrument(args.instrument, args.instrument_group)
generate_midi(
instrument,
key,
chord_progression,
pad,
octave=args.octave,
applause=args.applause,
)
def chord_root_to_scale_degree(root, key):
return progressions.determine([root], key,
True)[0].replace('i', 'I').replace('v', 'V')
def handle(self, argv=None):
"""
Main function.
Parses command, load settings and dispatches accordingly.
"""
help_message = "Please supply chord progression!. See --help for more options."
parser = argparse.ArgumentParser(
description=
'chords2midi - Create MIDI files from written chord progressions.\n'
)
parser.add_argument('progression',
metavar='U',
type=str,
nargs='*',
help=help_message)
parser.add_argument('-B',
'--bassline',
action='store_true',
default=False,
help='Throw an extra bassline on the pattern')
parser.add_argument('-b',
'--bpm',
type=int,
default=80,
help='Set the BPM (default 80)')
parser.add_argument('-t',
'--octave',
type=str,
default='4',
help='Set the octave(s) (ex: 3,4) (default 4)')
parser.add_argument('-i',
'--input',
type=str,
default=None,
help='Read from an input file.')
parser.add_argument('-k',
'--key',
type=str,
default='C',
help='Set the key (default C)')
parser.add_argument('-n',
'--notes',
type=int,
default=99,
help='Notes in each chord (default all)')
parser.add_argument('-d',
'--duration',
type=float,
default=1.0,
help='Set the chord duraction (default 1)')
parser.add_argument(
'-D',
'--directory',
action='store_true',
default=False,
help=
'Output the contents to the directory of the input progression.')
parser.add_argument(
'-H',
'--humanize',
type=float,
default=0.0,
help=
'Set the amount to "humanize" (strum) a chord, in ticks - try .11 (default 0.0)'
)
parser.add_argument(
'-o',
'--output',
type=str,
help=
'Set the output file path. Default is the current key and progression in the current location.'
)
parser.add_argument(
'-O',
'--offset',
type=float,
default=0.0,
help='Set the amount to offset each chord, in ticks. (default 0.0)'
)
parser.add_argument('-p',
'--pattern',
type=str,
default=None,
help='Set the pattern. Available patterns: ' +
(', '.join(patterns.keys())))
parser.add_argument(
'-r',
'--reverse',
action='store_true',
default=False,
help='Reverse a progression from C-D-E format into I-II-III format'
)
parser.add_argument('-v',
'--version',
action='store_true',
default=False,
help='Display the current version of chords2midi')
args = parser.parse_args(argv)
self.vargs = vars(args)
if self.vargs['version']:
version = pkg_resources.require("chords2midi")[0].version
print(version)
return
# Support `c2m I III V and `c2m I,III,V` formats.
if not self.vargs['input']:
if len(self.vargs['progression']) < 1:
print("You need to supply a progression! (ex I V vi IV)")
return
if len(self.vargs['progression']) < 2:
progression = self.vargs['progression'][0].split(',')
else:
progression = self.vargs['progression']
else:
with open(self.vargs['input']) as fn:
content = ''.join(fn.readlines()).strip()
content = content.replace('\n', ' ').replace(',', ' ')
progression = content.split(' ')
og_progression = progression
# If we're reversing, we don't need any of the MIDI stuff.
if self.vargs['reverse']:
result = ""
key = self.vargs['key']
for item in progression:
comps = pychord.Chord(item).components()
position = determine(comps, key, True)[0]
if 'M' in position:
position = position.upper()
position = position.replace('M', '')
if 'm' in position:
position = position.lower()
position = position.replace('m', '')
if 'B' in position:
position = position + "b"
position = position.replace('B', '')
result = result + position + " "
print result
return
track = 0
channel = 0
ttime = 0
duration = self.vargs['duration'] # In beats
tempo = self.vargs['bpm'] # In BPM
volume = 100 # 0-127, as per the MIDI standard
bar = 0
humanize_interval = self.vargs['humanize']
directory = self.vargs['directory']
num_notes = self.vargs['notes']
offset = self.vargs['offset']
key = self.vargs['key']
octaves = self.vargs['octave'].split(',')
root_lowest = self.vargs.get('root_lowest', False)
bassline = self.vargs['bassline']
pattern = self.vargs['pattern']
# Could be interesting to do multiple parts at once.
midi = MIDIFile(1)
midi.addTempo(track, ttime, tempo)
##
# Main generator
##
has_number = False
progression_chords = []
# Apply patterns
if pattern:
if pattern not in patterns.keys():
print("Invalid pattern! Must be one of: " +
(', '.join(patterns.keys())))
return
new_progression = []
input_progression = progression[:] # 2.7 copy
pattern_mask = patterns[pattern]
pattern_mask_index = 0
current_chord = None
while True:
pattern_instruction = pattern_mask[pattern_mask_index]
if pattern_instruction == "N":
if len(input_progression) == 0:
break
current_chord = input_progression.pop(0)
new_progression.append(current_chord)
elif pattern_instruction == "S":
new_progression.append(current_chord)
elif pattern_instruction == "X":
new_progression.append("X")
if pattern_mask_index == len(pattern_mask) - 1:
pattern_mask_index = 0
else:
pattern_mask_index = pattern_mask_index + 1
progression = new_progression
# We do this to allow blank spaces
for chord in progression:
# This is for # 'I', 'VI', etc
progression_chord = to_chords(chord, key)
if progression_chord != []:
has_number = True
# This is for 'C', 'Am', etc.
if progression_chord == []:
try:
progression_chord = [pychord.Chord(chord).components()]
except Exception:
# This is an 'X' input
progression_chord = [None]
chord_info = {}
chord_info['notes'] = progression_chord[0]
if has_number:
chord_info['number'] = chord
else:
chord_info['name'] = chord
if progression_chord[0]:
chord_info['root'] = progression_chord[0][0]
else:
chord_info['root'] = None
progression_chords.append(chord_info)
# For each input..
previous_pitches = []
for chord_index, chord_info in enumerate(progression_chords):
# Unpack object
chord = chord_info['notes']
# NO_OP
if chord == None:
bar = bar + 1
continue
root = chord_info['root']
root_pitch = pychord.utils.note_to_val(
notes.int_to_note(notes.note_to_int(root)))
# Reset internals
humanize_amount = humanize_interval
pitches = []
all_new_pitches = []
# Turns out this algorithm was already written in the 1800s!
# https://en.wikipedia.org/wiki/Voice_leading#Common-practice_conventions_and_pedagogy
# a) When a chord contains one or more notes that will be reused in the chords immediately following, then these notes should remain, that is retained in the respective parts.
# b) The parts which do not remain, follow the law of the shortest way (Gesetze des nachsten Weges), that is that each such part names the note of the following chord closest to itself if no forbidden succession XXX GOOD NAME FOR A BAND XXX arises from this.
# c) If no note at all is present in a chord which can be reused in the chord immediately following, one must apply contrary motion according to the law of the shortest way, that is, if the root progresses upwards, the accompanying parts must move downwards, or inversely, if the root progresses downwards, the other parts move upwards and, in both cases, to the note of the following chord closest to them.
root = None
for i, note in enumerate(chord):
# Sanitize notes
sanitized_notes = notes.int_to_note(notes.note_to_int(note))
pitch = pychord.utils.note_to_val(sanitized_notes)
if i == 0:
root = pitch
if root:
if root_lowest and pitch < root: # or chord_index is 0:
pitch = pitch + 12 # Start with the root lowest
all_new_pitches.append(pitch)
# Reuse notes
if pitch in previous_pitches:
pitches.append(pitch)
no_melodic_fluency = False # XXX: vargify
if previous_pitches == [] or all_new_pitches == [] or pitches == [] or no_melodic_fluency:
pitches = all_new_pitches
else:
# Detect the root direction
root_upwards = None
if pitches[0] >= all_new_pitches[0]:
root_upwards = True
else:
root_upwards = False
# Move the shortest distance
if pitches != []:
new_remaining_pitches = list(all_new_pitches)
old_remaining_pitches = list(previous_pitches)
for i, new_pitch in enumerate(all_new_pitches):
# We're already there
if new_pitch in pitches:
new_remaining_pitches.remove(new_pitch)
old_remaining_pitches.remove(new_pitch)
continue
# Okay, so need to find the overall shortest distance from the remaining pitches - including their permutations!
while len(new_remaining_pitches) > 0:
nearest_distance = 9999
previous_index = None
new_index = None
pitch_to_add = None
for i, pitch in enumerate(new_remaining_pitches):
# XXX: DRY
# The Pitch
pitch_to_test = pitch
nearest = min(old_remaining_pitches,
key=lambda x: abs(x - pitch_to_test))
old_nearest_index = old_remaining_pitches.index(
nearest)
if nearest < nearest_distance:
nearest_distance = nearest
previous_index = old_nearest_index
new_index = i
pitch_to_add = pitch_to_test
# +12
pitch_to_test = pitch + 12
nearest = min(old_remaining_pitches,
key=lambda x: abs(x - pitch_to_test))
old_nearest_index = old_remaining_pitches.index(
nearest)
if nearest < nearest_distance:
nearest_distance = nearest
previous_index = old_nearest_index
new_index = i
pitch_to_add = pitch_to_test
# -12
pitch_to_test = pitch - 12
nearest = min(old_remaining_pitches,
key=lambda x: abs(x - pitch_to_test))
old_nearest_index = old_remaining_pitches.index(
nearest)
if nearest < nearest_distance:
nearest_distance = nearest
previous_index = old_nearest_index
new_index = i
pitch_to_add = pitch_to_test
# Before we add it - just make sure that there isn't a better place for it.
pitches.append(pitch_to_add)
del old_remaining_pitches[previous_index]
del new_remaining_pitches[new_index]
# This is for the C E7 type scenario
if len(old_remaining_pitches) == 0:
for x, extra_pitch in enumerate(
new_remaining_pitches):
pitches.append(extra_pitch)
del new_remaining_pitches[x]
# Final check - can the highest and lowest be safely folded inside?
max_pitch = max(pitches)
min_pitch = min(pitches)
index_max = pitches.index(max_pitch)
folded_max = max_pitch - 12
if (folded_max > min_pitch) and (folded_max
not in pitches):
pitches[index_max] = folded_max
max_pitch = max(pitches)
min_pitch = min(pitches)
index_min = pitches.index(min_pitch)
folded_min = min_pitch + 12
if (folded_min < max_pitch) and (folded_min
not in pitches):
pitches[index_min] = folded_min
# Make sure the average can't be improved
# XXX: DRY
if len(previous_pitches) != 0:
previous_average = sum(previous_pitches) / len(
previous_pitches)
# Max
max_pitch = max(pitches)
min_pitch = min(pitches)
index_max = pitches.index(max_pitch)
folded_max = max_pitch - 12
current_average = sum(pitches) / len(pitches)
hypothetical_pitches = list(pitches)
hypothetical_pitches[index_max] = folded_max
hypothetical_average = sum(hypothetical_pitches) / len(
hypothetical_pitches)
if abs(previous_average -
hypothetical_average) <= abs(previous_average -
current_average):
pitches[index_max] = folded_max
# Min
max_pitch = max(pitches)
min_pitch = min(pitches)
index_min = pitches.index(min_pitch)
folded_min = min_pitch + 12
current_average = sum(pitches) / len(pitches)
hypothetical_pitches = list(pitches)
hypothetical_pitches[index_min] = folded_min
hypothetical_average = sum(hypothetical_pitches) / len(
hypothetical_pitches)
if abs(previous_average -
hypothetical_average) <= abs(previous_average -
current_average):
pitches[index_min] = folded_min
# Apply contrary motion
else:
print("Applying contrary motion!")
for i, new_pitch in enumerate(all_new_pitches):
if i == 0:
pitches.append(new_pitch)
continue
# Root upwards, the rest move down.
if root_upwards:
if new_pitch < previous_pitches[i]:
pitches.append(new_pitch)
else:
pitches.append(new_pitch - 12)
else:
if new_pitch > previous_pitches[i]:
pitches.append(new_pitch)
else:
pitches.append(new_pitch + 12)
# Bassline
if bassline:
pitches.append(root_pitch - 24)
# Melody
# Octave is a simple MIDI offset counter
for octave in octaves:
for note in pitches:
pitch = int(note) + (int(octave.strip()) * 12)
# Don't humanize bassline note
if bassline and (pitches.index(note) == len(pitches) - 1):
midi_time = offset + bar
else:
midi_time = offset + bar + humanize_amount
# Write the note
midi.addNote(track=track,
channel=channel,
pitch=pitch,
time=midi_time,
duration=duration,
volume=volume)
humanize_amount = humanize_amount + humanize_interval
if i + 1 >= num_notes:
break
bar = bar + 1
previous_pitches = pitches
##
# Output
##
if self.vargs['output']:
filename = self.vargs['output']
elif self.vargs['input']:
filename = self.vargs['input'].replace('.txt', '.mid')
else:
if has_number:
key_prefix = key + '-'
else:
key_prefix = ''
filename = key_prefix + '-'.join(og_progression) + '-' + str(tempo)
if bassline:
filename = filename + "-bassline"
if pattern:
filename = filename + "-" + pattern
if os.path.exists(filename):
filename = key_prefix + '-'.join(og_progression) + '-' + str(
tempo) + '-' + str(int(time.time()))
filename = filename + '.mid'
if directory:
directory_to_create = '-'.join(og_progression)
try:
os.makedirs(directory_to_create)
except OSError as exc: # Python >2.5
if exc.errno == errno.EEXIST and os.path.isdir(
directory_to_create):
pass
else:
raise
filename = directory_to_create + '/' + filename
with open(filename, "wb") as output_file:
midi.writeFile(output_file)