def onset(position, metadata): """Calculate the ideal onset of this position given the tempo in metadata""" scale = 1000000 m = meter.getMeter(metadata) bpm = metadata['bpm'] beatlength = scale/(bpm/60.0) beats = position / float(m.quarters_per_beat()) return beats * beatlength
def __init__(self, annotation, notes, metadata):
from jazzr.rhythm import meter
self.annotation = annotation
self.notes = notes
self.metadata = metadata
self.bpm = metadata['bpm']
self.name = metadata['name']
self.meter = meter.getMeter(metadata)
# Onset units per second (1000000 = onsets in microseconds)
self.scale = 1000000
def deviation(position, onset, metadata): """Calculate the proportion of a beat that the given onset deviates from the ideal onset corresponding to the given position.""" # Onset units per second (1000000 = onsets in microseconds) scale = 1000000 m = meter.getMeter(metadata) bpm = metadata['bpm'] beatlength = scale/(bpm/60.0) beats = position / float(m.quarters_per_beat()) beat_onset = beats * beatlength deviation = onset - beat_onset return deviation / beatlength
def split(annotation, index, metadata):
"""Split notes and rests that span across multiple bars in separate
(bound) notes and rests."""
(position, x, pitch, type) = annotation[index]
m = meter.getMeter(metadata)
if not type in [types.REST, types.NOTE]:
return [(position, index, pitch, type)]
ql = quarterLength(annotation, index, metadata)
current = position
remainder = ql
result = []
barlength = m.quarters_per_bar()
while bar(current, metadata) != bar(current + remainder, metadata):
diff = (bar(current, metadata)+1)*barlength - current
result.append((current, index, pitch, type))
remainder -= diff
current += diff
if remainder > 0:
result.append((current, index, pitch, type))
return result
def barposition(position, metadata): """Calculate the position in quarter notes relative to the beginning of the bar.""" m = meter.getMeter(metadata) beats = position / float(m.quarters_per_beat()) return beats - m.beatspb * (beats // m.beatspb)
def bar(position, metadata): """Return the bar in which this position occurs""" m = meter.getMeter(metadata) beats = position / float(m.quarters_per_beat()) return int(beats // m.beatspb)