christopher@6: # -*- coding: utf-8 -*-
christopher@6: """
christopher@6: Created on Sat Mar 21 22:19:52 2015
christopher@6: 
christopher@6: @author: christopherh
christopher@6: """
christopher@6: 
christopher@6: from midiparser import MidiFile, MidiTrack, DeltaTime, MidiEvent
christopher@6: #from RhythmParser import Bar
christopher@6: 
christopher@10: from music_objects import *
christopher@6: 
christopher@6: 
christopher@6: 
christopher@6: 
christopher@6: 
christopher@10: def read_midi_file(filename):
christopher@6: 	""" open and read a MIDI file, return a MidiFile object """
christopher@6: 
christopher@6: 	#create a midifile object, open and read a midi file
christopher@6: 	midiFile = MidiFile()
christopher@6: 	midiFile.open(filename, 'rb')
christopher@6: 	midiFile.read()
christopher@6: 	midiFile.close()
christopher@6: 
christopher@6: 	return midiFile
christopher@6: 
christopher@10: # def get_bars(midiFile, trackindex=1):
christopher@10: # 	""" returns a list of bar objects from a MidiFile object """
christopher@6: 
christopher@10: # 	# select a track to extract (default = 1, ignoring dummy track 0)
christopher@10: # 	track = midiFile.tracks[trackindex] 
christopher@10: # 	eventIndex = 0
christopher@10: # 	numNotes = 0
christopher@6: 
christopher@10: # 	noteonlist = []
christopher@10: # 	noteOnFound==True
christopher@6: 
christopher@10: # 	while noteOnFound==True:
christopher@10: # 		(noteOnIndex, noteOnDelta, noteOnFound) = self.find_event(track, eventIndex, lambda e: e.type == 'NOTE_ON')
christopher@10: # 		noteEvent = track.events[noteOnIndex]
christopher@10: # 		eventIndex = noteOnIndex + 1
christopher@6:             	
christopher@6: 
christopher@6: 
christopher@6: 
christopher@6: 
christopher@6: 
christopher@10: def find_event(track, eventStartIndex, lambdaExpr):
christopher@6: 	'''
christopher@6: 	From code by Csaba Sulyok:
christopher@6: 	Finds MIDI event based on lambda expression, starting from a given index.
christopher@6: 	Returns a tuple of the following 3 elements:
christopher@6: 	1. event index where the lambda expression is true
christopher@6: 	2. aggregate delta time from event start index until the found event
christopher@6: 	3. flag whether or not any value was found, or we've reached the end of the event queue
christopher@6: 	'''
christopher@6: 
christopher@10: 	eventIndex = eventStartIndex
christopher@6: 	deltaTime = 0
christopher@10: 	while eventIndex < len(track.events) and not lambdaExpr(track.events[eventIndex]):
christopher@10: 	    if track.events[eventIndex].type == 'DeltaTime':
christopher@10: 	        deltaTime += track.events[eventIndex].time
christopher@10: 	    eventIndex += 1
christopher@6: 
christopher@10: 	success = eventIndex < len(track.events)
christopher@10: 	return (eventIndex, deltaTime, success)
christopher@6: 
christopher@6: