csong@0: '''
csong@0: Author: Chunyang Song
csong@0: Institution: Centre for Digital Music, Queen Mary University of London
csong@0: 
csong@0: ** Pressing's model **
csong@0: 
csong@0: Algorithm:
csong@0: 
csong@0: Only applicable to simple rhtyhms.
csong@0: 
csong@0: Generate hierarchical metrical structure for rhythms, they way as same as LHL model;
csong@0: 
csong@0: 
csong@0: '''
csong@0: 
csong@0: def subdivide(sequence, segments_num):
csong@0: 	subSeq = []
csong@0: 	if len(sequence) % segments_num != 0:
csong@0: 		print 'Error: rhythm segment cannot be equally subdivided '
csong@0: 	else:
csong@0: 		n = len(sequence) / segments_num
csong@0: 		start , end = 0, n
csong@0: 		for i in range(segments_num):
csong@0: 			subSeq.append(sequence[start : end])
csong@0: 			start = end
csong@0: 			end = end + n
csong@0: 	
csong@0: 	return subSeq
csong@0: 
csong@0: # To check whether there is a need to continue subdividing and measuring
csong@0: def checkContinue(sequence, division):
csong@0: 	isContinue = False
csong@0: 	if len(sequence) % division == 0:
csong@0: 		subs = subdivide (sequence, division)
csong@0: 		
csong@0: 		for s in subs:
csong@0: 			if 1 in s[1:]:	# If there are still onsets in-between the divisions
csong@0: 				isContinue = True
csong@0: 	else:
csong@0: 		print 'Error: the sequence cannot be equally subdivided!'
csong@0: 	return isContinue
csong@0: 
csong@0: def timeSpanTranscribe(sequence):
csong@0: 	l = len(sequence)
csong@0: 	transcribe = []
csong@0: 
csong@0: 	if not (1 in sequence):  # Full rest
csong@0: 		transcribe = [0]
csong@0: 	else:
csong@0: 		divisor = 1
csong@0: 		while True:
csong@0: 			if l%divisor != 0:
csong@0: 				divisor = divisor + 1
csong@0: 			else:
csong@0: 				sampleStep = l/divisor # how many digits in each segment, divisor also represents the number of segments
csong@0: 				template = (([1] + [0]*(sampleStep-1) ) * divisor )
csong@0: 
csong@0: 				sampled = []
csong@0: 				for i in range(l):
csong@0: 					sampled.append(sequence[i] and template[i])
csong@0: 
csong@0: 				if sequence == sampled:
csong@0: 					break
csong@0: 				else:
csong@0: 					divisor = divisor + 1
csong@0: 
csong@0: 		subs = subdivide(sequence, divisor)
csong@0: 		for s in subs:
csong@0: 			transcribe.append(s[0])
csong@0: 
csong@0: 	return transcribe
csong@0: 
csong@0: # Identify the type of rhythm sequence : 0- null; 1-filled; 2-run; 3-upbeat; 5-syncopated
csong@0: def syncType (sequence, followed_event):
csong@0: 	
csong@0: 	# Null is full rest or only one single on-beat note, therefore no 0 in sequence[1:]
csong@0: 	if not(1 in sequence[1:]) : 
csong@0: 		syncType = 0 
csong@0: 
csong@0: 	else:
csong@0: 		ts = timeSpanTranscribe(sequence)
csong@0: 
csong@0: 		# Filled is equally spaced onsets, therefore all 1s in the time span transcribe of the sequence
csong@0: 		if not(0 in ts ):
csong@0: 			syncType = 1  
csong@0: 		# Run is either starting with 1 and end with 0 in time span, or starting with 1 if next bar starts with 0
csong@0: 		elif ts[0] == 1 and ts[-1] == 0:
csong@0: 			syncType = 2		
csong@0: 		elif followed_event ==0 and ts[0] == 1:
csong@0: 			syncType = 2
csong@0: 		# Upbeat requires next bars starting with 1 and at least the last event in time span is 1
csong@0: 		elif followed_event == 1 and ts[-1] == 1: 
csong@0: 			syncType = 3
csong@0: 		# Syncopated start and end off-beat		
csong@0: 		elif sequence[0] == 0:
csong@0: 			syncType = 5
csong@0: 		else:
csong@0: 			print 'Error: un-recognizable syncopation type ', sequence
csong@0: 			syncType = None
csong@0: 
csong@0: 	return syncType
csong@0: 
csong@0: def createHierarchy(rhythm, time_sig, bar):
csong@0: 	h = [] # A list of lists to record syncopation type(s) in each hierarchy level across bars
csong@0: 	s_bar = subdivide (rhythm, bar)
csong@0: 	
csong@0: 	if '4/4' in time_sig:
csong@0: 		 
csong@0: 		for i in range(bar):
csong@0: 			bar_level = s_bar[i]
csong@0: 
csong@0: 			if i == bar -1:
csong@0: 				followed_event = s_bar[0][0]
csong@0: 			else:
csong@0: 				followed_event = s_bar[i+1][0]
csong@0: 			
csong@0: 			h. append ( [syncType(bar_level, followed_event)] )  # Indentify syncopation type at bar level 
csong@0: 
csong@0: 		if checkContinue(rhythm, 2*bar):
csong@0: 
csong@0: 			for i in range(bar):
csong@0: 				s_halfBar = subdivide (s_bar[i], 2)
csong@0: 				halfBar_h = []
csong@0: 
csong@0: 				for j in range(2):
csong@0: 					halfBar_level = s_halfBar[j]
csong@0: 
csong@0: 					if j == 1:
csong@0: 						followed_event = s_halfBar[0][0]
csong@0: 					else:
csong@0: 						followed_event = s_halfBar[j+1][0]
csong@0: 
csong@0: 					halfBar_h.append (syncType (halfBar_level , followed_event))
csong@0: 
csong@0: 				h.append(halfBar_h)
csong@0: 
csong@0: 			if checkContinue(rhythm, 4*bar):
csong@0: 			
csong@0: 				for i in range(bar):
csong@0: 					s_quarter = subdivide (s_bar[i], 4)
csong@0: 					quarter_h = []
csong@0: 
csong@0: 					for j in range(4):			
csong@0: 						quarter_level = s_quarter [j]
csong@0: 
csong@0: 						if j == 3:
csong@0: 							followed_event = s_quarter[0][0]
csong@0: 						else:
csong@0: 							followed_event = s_quarter[j+1][0]
csong@0: 
csong@0: 						quarter_h. append ( syncType (quarter_level , followed_event) )	# quarter note level
csong@0: 
csong@0: 					h.append(quarter_h)
csong@0: 
csong@0: 				if checkContinue( rhythm, 8*bar):
csong@0: 					
csong@0: 					for i in range(bar):
csong@0: 						s_eighth = subdivide (s_bar[i], 8)
csong@0: 						eighth_h = []
csong@0: 
csong@0: 						for j in range(8):
csong@0: 							eighth_level = s_eighth [j]
csong@0: 
csong@0: 							if j == 7:
csong@0: 								followed_event = eighth_level[0][0]
csong@0: 							else:
csong@0: 								followed_event = eighth_level[j+1][0]
csong@0: 
csong@0: 							eighth_h.append (syncType (eighth_level, followed_event) )
csong@0: 					
csong@0: 						h.append(eighth_h)
csong@0: 
csong@0: 
csong@0: 	elif '3/4' in time_sig:	
csong@0: 		size_bar = len(s_bar)
csong@0: 		for i in range(size_bar):
csong@0: 			bar_level = s_bar[i]
csong@0: 
csong@0: 			quarter_h = []
csong@0: 			eighth_h = []
csong@0: 			
csong@0: 			if i == size_bar -1:
csong@0: 				followed_event = s_bar[0][0]
csong@0: 			else:
csong@0: 				followed_event = s_bar[i+1][0]
csong@0: 			
csong@0: 			h. append ( [syncType(bar_level, followed_event)] )  # Indentify syncopation type at bar level 
csong@0: 
csong@0: 			if checkContinue(bar_level, 3):
csong@0: 				s_quarter = subdivide (bar_level, 3)
csong@0: 				size_quarter = len(s_quarter)
csong@0: 				
csong@0: 				for j in range(size_quarter):
csong@0: 					quarter_level = s_quarter [j]
csong@0: 
csong@0: 					if j == size_quarter -1:
csong@0: 						followed_event = s_quarter[0][0]
csong@0: 					else:
csong@0: 						followed_event = s_quarter[j+1][0]
csong@0: 
csong@0: 					quarter_h. append ( syncType (quarter_level , followed_event) )	# quarter note level
csong@0: 
csong@0: 					if checkContinue( quarter_level, 2):
csong@0: 						s_eighth = subdivide (quarter_level, 2)	# eighth note level
csong@0: 						size_eighth = len(s_eighth)
csong@0: 
csong@0: 						for k in range(size_eighth):
csong@0: 							eighth_level = s_eighth [k]
csong@0: 
csong@0: 							if k == size_eighth - 1:
csong@0: 								followed_event = eighth_level[0][0]
csong@0: 							else:
csong@0: 								followed_event = eighth_level[k+1][0]
csong@0: 
csong@0: 							eighth_h.append (syncType (eighth_level, followed_event) )
csong@0: 						h.append(eighth_h)
csong@0: 
csong@0: 				h.append(quarter_h)
csong@0: 		
csong@0: 
csong@0: 	elif '6/8' in time_sig:		
csong@0: 		for i in range(bar):
csong@0: 			bar_level = s_bar[i]
csong@0: 			
csong@0: 			if i == bar -1:
csong@0: 				followed_event = s_bar[0][0]
csong@0: 			else:
csong@0: 				followed_event = s_bar[i+1][0]
csong@0: 			
csong@0: 			h. append ( [syncType(bar_level, followed_event)] )  # Indentify syncopation type at bar level 
csong@0: 			
csong@0: 		if checkContinue(rhythm, 2*bar):
csong@0: 			
csong@0: 			for i in range(bar):
csong@0: 				s_halfBar = subdivide (s_bar[i], 2)
csong@0: 				halfBar_h = []
csong@0: 
csong@0: 				for j in range(2):
csong@0: 					halfBar_level = s_halfBar [j]
csong@0: 					
csong@0: 					if j == 1:
csong@0: 						followed_event = s_halfBar[0][0]
csong@0: 					else:
csong@0: 						followed_event = s_halfBar[j+1][0]
csong@0: 
csong@0: 					halfBar_h. append ( syncType (halfBar_level , followed_event) )	
csong@0: 
csong@0: 				h.append(halfBar_h)
csong@0: 
csong@0: 			if checkContinue( rhythm, 6*bar):
csong@0: 				
csong@0: 				for i in range(bar):	
csong@0: 					s_eighth = subdivide (s_bar[i], 6)	# eighth note level
csong@0: 					eighth_h = []
csong@0: 					
csong@0: 					for j in range(6):
csong@0: 						eighth_level = s_eighth [j]
csong@0: 
csong@0: 						if j == 5:
csong@0: 							followed_event = eighth_level[0][0]
csong@0: 						else:
csong@0: 							followed_event = eighth_level[j+1][0]
csong@0: 
csong@0: 						eighth_h.append (syncType (eighth_level, followed_event) )
csong@0: 					
csong@0: 					h.append(eighth_h)
csong@0: 
csong@0: 	else:
csong@0: 		print 'This time signature is not defined. Choose between 4/4, 3/4 or 6/8'
csong@0: 
csong@0: 	return h
csong@0: 
csong@0: 
csong@0: def pressing(rhythm, time_sig, category, bar):
csong@0: 	sync_oneLevel = []
csong@0: 
csong@0: 	if 'poly' in category:
csong@0: 		return -1
csong@0: 
csong@0: 	else:
csong@0: 		hierarchy = createHierarchy(rhythm, time_sig, bar)
csong@0: 		# print 'h', hierarchy
csong@0: 
csong@0: 		if len(hierarchy) != 0:
csong@0: 			for h in hierarchy:
csong@0: 				sync_oneLevel.append (sum(h) / float(len(h)) )
csong@0: 			
csong@0: 			# Syncopation is the sum of averaged syncopation values of each level
csong@0: 			syncopation = sum (sync_oneLevel)
csong@0: 			
csong@0: 		else:
csong@0: 			syncopation = 0
csong@0: 
csong@0: 		return syncopation 
csong@0: 
csong@0: 
csong@0: # Retrieve the stimuli
csong@0: # f = file('stimuli.txt')
csong@0: f = file('stimuli_34only.txt')
csong@0: 
csong@0: #Calculate syncopation for each rhythm pattern
csong@0: while True:
csong@0: 	line = f.readline().split(';')
csong@0: 	if len(line) == 1:
csong@0: 		 break
csong@0: 	else:
csong@0: 		sti_name = line[0]
csong@0: 		rhythmString = line[1].split()
csong@0: 		time_sig = line[2]
csong@0: 		category = line[3]
csong@0: 		bar = int([4])
csong@0: 		
csong@0: 		rhythm = map(int,rhythmString[0].split(','))
csong@0: 
csong@0: 		print sti_name, pressing(rhythm, time_sig, category, bar)
csong@0: