diff Example VamPy plugins/test/PyMFCC_oldstyle.py @ 37:27bab3a16c9a vampy2final

new branch Vampy2final

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Example VamPy plugins/test/PyMFCC_oldstyle.py	Mon Oct 05 11:28:00 2009 +0000
@@ -0,0 +1,361 @@
+'''PyMFCC_oldstyle.py - This example Vampy plugin demonstrates
+how to return sprectrogram-like features.
+
+This plugin uses backward compatible syntax and 
+no extension module.
+
+Centre for Digital Music, Queen Mary University of London.
+Copyright 2006 Gyorgy Fazekas, QMUL. 
+(See Vamp API for licence information.)
+
+Constants for Mel frequency conversion and filter 
+centre calculation are taken from the GNU GPL licenced 
+Freespeech library. Copyright (C) 1999 Jean-Marc Valin
+'''
+
+import sys,numpy
+from numpy import log,exp,floor,sum
+from numpy import *       
+from numpy.fft import *
+
+
+class melScaling(object):
+
+	def __init__(self,sampleRate,inputSize,numBands,minHz = 0,maxHz = None):
+		'''Initialise frequency warping and DCT matrix. 
+		Parameters:
+		sampleRate: audio sample rate
+		inputSize: length of magnitude spectrum (half of FFT size assumed)
+		numBands: number of mel Bands (MFCCs)
+		minHz: lower bound of warping  (default = DC)
+		maxHz: higher bound of warping (default = Nyquist frequency)
+		'''
+		self.sampleRate = sampleRate
+		self.NqHz = sampleRate / 2.0
+		self.minHz = minHz
+		if maxHz is None : maxHz = self.NqHz
+		self.maxHz = maxHz
+		self.inputSize = inputSize
+		self.numBands = numBands
+		self.valid = False
+		self.updated = False
+		# print '\n\n>>Plugin initialised with sample rate: %s<<\n\n' %self.sampleRate
+		# print 'minHz:%s\nmaxHz:%s\n' %(self.minHz,self.maxHz)
+		
+		
+	def update(self): 
+		# make sure this will run only once if called from a vamp process
+		
+		if self.updated: return self.valid
+		self.updated = True
+		self.valid = False
+		print 'Updating parameters and recalculating filters: '
+		print 'Nyquist: ',self.NqHz
+		
+		if self.maxHz > self.NqHz : 
+			raise Exception('Maximum frequency must be smaller than the Nyquist frequency')
+		
+		self.maxMel = 1000*log(1+self.maxHz/700.0)/log(1+1000.0/700.0)
+		self.minMel = 1000*log(1+self.minHz/700.0)/log(1+1000.0/700.0)
+		print 'minHz:%s\nmaxHz:%s\nminMel:%s\nmaxMel:%s\n' %(self.minHz,self.maxHz,self.minMel,self.maxMel)
+		self.filterMatrix = self.getFilterMatrix(self.inputSize,self.numBands)
+		self.DCTMatrix = self.getDCTMatrix(self.numBands)
+		self.filterIter = self.filterMatrix.__iter__()
+		self.valid = True
+		return self.valid
+		
+		# try :
+		# 	self.maxMel = 1000*log(1+self.maxHz/700.0)/log(1+1000.0/700.0)
+		# 	self.minMel = 1000*log(1+self.minHz/700.0)/log(1+1000.0/700.0)
+		# 	self.filterMatrix = self.getFilterMatrix(self.inputSize,self.numBands)
+		# 	self.DCTMatrix = self.getDCTMatrix(self.numBands)
+		# 	self.filterIter = self.filterMatrix.__iter__()
+		# 	self.valid = True
+		# 	return True
+		# except :
+		# 	print "Invalid parameter setting encountered in MelScaling class."
+		# 	return False
+		# return True
+		
+	def getFilterCentres(self,inputSize,numBands):
+		'''Calculate Mel filter centres around FFT bins.
+		This function calculates two extra bands at the edges for
+		finding the starting and end point of the first and last 
+		actual filters.'''
+		centresMel = numpy.array(xrange(numBands+2)) * (self.maxMel-self.minMel)/(numBands+1) + self.minMel
+		centresBin = numpy.floor(0.5 + 700.0*inputSize*(exp(centresMel*log(1+1000.0/700.0)/1000.0)-1)/self.NqHz)
+		return numpy.array(centresBin,int)
+		
+	def getFilterMatrix(self,inputSize,numBands):
+		'''Compose the Mel scaling matrix.'''
+		filterMatrix = numpy.zeros((numBands,inputSize))
+		self.filterCentres = self.getFilterCentres(inputSize,numBands)
+		for i in xrange(numBands) :
+			start,centre,end = self.filterCentres[i:i+3]
+			self.setFilter(filterMatrix[i],start,centre,end)
+		return filterMatrix.transpose()
+
+	def setFilter(self,filt,filterStart,filterCentre,filterEnd):
+		'''Calculate a single Mel filter.'''
+		k1 = numpy.float32(filterCentre-filterStart)
+		k2 = numpy.float32(filterEnd-filterCentre)
+		up = (numpy.array(xrange(filterStart,filterCentre))-filterStart)/k1
+		dn = (filterEnd-numpy.array(xrange(filterCentre,filterEnd)))/k2
+		filt[filterStart:filterCentre] = up
+		filt[filterCentre:filterEnd] = dn
+						
+	def warpSpectrum(self,magnitudeSpectrum):
+		'''Compute the Mel scaled spectrum.'''
+		return numpy.dot(magnitudeSpectrum,self.filterMatrix)
+		
+	def getDCTMatrix(self,size):
+		'''Calculate the square DCT transform matrix. Results are 
+		equivalent to Matlab dctmtx(n) but with 64 bit precision.'''
+		DCTmx = numpy.array(xrange(size),numpy.float64).repeat(size).reshape(size,size)
+		DCTmxT = numpy.pi * (DCTmx.transpose()+0.5) / size
+		DCTmxT = (1.0/sqrt( size / 2.0)) * cos(DCTmx * DCTmxT)
+		DCTmxT[0] = DCTmxT[0] * (sqrt(2.0)/2.0)
+		return DCTmxT
+		
+	def dct(self,data_matrix):
+		'''Compute DCT of input matrix.'''
+		return numpy.dot(self.DCTMatrix,data_matrix)
+		
+	def getMFCCs(self,warpedSpectrum,cn=True):
+		'''Compute MFCC coefficients from Mel warped magnitude spectrum.'''
+		mfccs=self.dct(numpy.log(warpedSpectrum))
+		if cn is False : mfccs[0] = 0.0
+		return mfccs
+	
+
+class PyMFCC_oldstyle(melScaling): 
+	
+	def __init__(self,inputSampleRate):
+		self.vampy_flags = 1 # vf_DEBUG = 1
+		self.m_inputSampleRate = inputSampleRate 
+		self.m_stepSize = 1024
+		self.m_blockSize = 2048
+		self.m_channels = 1
+		self.numBands = 40
+		self.cnull = 1
+		melScaling.__init__(self,int(self.m_inputSampleRate),self.m_blockSize/2,self.numBands)
+		
+	def initialise(self,channels,stepSize,blockSize):
+		self.m_channels = channels
+		self.m_stepSize = stepSize		
+		self.m_blockSize = blockSize
+		self.window = numpy.hamming(blockSize)
+		melScaling.__init__(self,int(self.m_inputSampleRate),self.m_blockSize/2,self.numBands)
+		return True
+	
+	def getMaker(self):
+		return 'Vampy Test Plugins'
+		
+	def getCopyright(self):
+		return 'Plugin By George Fazekas'
+	
+	def getName(self):
+		return 'Vampy Old Style MFCC Plugin'
+		
+	def getIdentifier(self):
+		return 'vampy-mfcc-test-old'
+
+	def getDescription(self):
+		return 'A simple MFCC plugin. (using the old syntax)'
+	
+	def getMaxChannelCount(self):
+		return 1
+		
+	def getInputDomain(self):
+		return 'TimeDomain'
+		
+	def getPreferredBlockSize(self):
+		return 2048
+		
+	def getPreferredStepSize(self):
+		return 512
+			
+	def getOutputDescriptors(self):
+
+		Generic={
+		'hasFixedBinCount':True,
+		'binCount':int(self.numBands)-self.cnull,
+		'hasKnownExtents':False,
+		'isQuantized':True,
+		'sampleType':'OneSamplePerStep'
+		}
+		
+		MFCC=Generic.copy()
+		MFCC.update({
+		'identifier':'mfccs',
+		'name':'MFCCs',
+		'description':'MFCC Coefficients',
+		'binNames':map(lambda x: 'C '+str(x),range(self.cnull,int(self.numBands))),
+		'unit':''		
+		})
+		
+		warpedSpectrum=Generic.copy()
+		warpedSpectrum.update({
+		'identifier':'warped-fft',
+		'name':'Mel Scaled Spectrum',
+		'description':'Mel Scaled Magnitide Spectrum',
+		'unit':'Mel'
+		})
+		
+		melFilter=Generic.copy()
+		melFilter.update({
+		'identifier':'mel-filter',
+		'name':'Mel Filter Matrix',
+		'description':'Returns the created filter matrix.',
+		'sampleType':'FixedSampleRate',
+		'sampleRate':self.m_inputSampleRate/self.m_stepSize,
+		'unit':''
+		})
+				
+		return [MFCC,warpedSpectrum,melFilter]
+
+	def getParameterDescriptors(self):
+		melbands = {
+		'identifier':'melbands',
+		'name':'Number of bands (coefficients)',
+		'description':'Set the number of coefficients.',
+		'unit':'',
+		'minValue':2.0,
+		'maxValue':128.0,
+		'defaultValue':40.0,
+		'isQuantized':True,
+		'quantizeStep':1.0
+		}
+		
+		cnull = {
+		'identifier':'cnull',
+		'name':'Return C0',
+		'description':'Select if the DC coefficient is required.',
+		'unit':'',
+		'minValue':0.0,
+		'maxValue':1.0,
+		'defaultValue':0.0,
+		'isQuantized':True,
+		'quantizeStep':1.0
+		}
+		
+		minHz = {
+		'identifier':'minHz',
+		'name':'minimum frequency',
+		'description':'Set the lower frequency bound.',
+		'unit':'Hz',
+		'minValue':0.0,
+		'maxValue':24000.0,
+		'defaultValue':0.0,
+		'isQuantized':True,
+		'quantizeStep':1.0
+		}
+				
+		maxHz = {
+		'identifier':'maxHz',
+		'name':'maximum frequency',
+		'description':'Set the upper frequency bound.',
+		'unit':'Hz',
+		'minValue':100.0,
+		'maxValue':24000.0,
+		'defaultValue':11025.0,
+		'isQuantized':True,
+		'quantizeStep':100.0
+		}
+		
+		return [melbands,minHz,maxHz,cnull]
+
+	def setParameter(self,paramid,newval):
+		self.valid = False
+		if paramid == 'minHz' :
+			if newval < self.maxHz and newval < self.NqHz :
+				self.minHz = float(newval)
+			print 'minHz: ', self.minHz
+		if paramid == 'maxHz' :
+			print 'trying to set maxHz to: ',newval
+			if newval < self.NqHz and newval > self.minHz+1000 :
+				self.maxHz = float(newval)
+			else :
+				self.maxHz = self.NqHz
+			print 'set to: ',self.maxHz
+		if paramid == 'cnull' :
+			self.cnull = int(not int(newval))
+		if paramid == 'melbands' :
+			self.numBands = int(newval)
+		return 
+				
+	def getParameter(self,paramid):
+		if paramid == 'minHz' :
+			return float(self.minHz)
+		if paramid == 'maxHz' :
+			return float(self.maxHz)
+		if paramid == 'cnull' :
+			return float(not int(self.cnull))
+		if paramid == 'melbands' :
+			return float(self.numBands)
+		else:
+			return 0.0
+			
+	def processN(self,membuffer,frameSampleStart):
+		
+		# recalculate the filter and DCT matrices if needed
+		if not self.update() : return []
+
+		fftsize = self.m_blockSize
+		audioSamples = frombuffer(membuffer[0],float32)
+
+		complexSpectrum = fft(self.window*audioSamples,fftsize)
+		#complexSpectrum =  frombuffer(membuffer[0],complex64,-1,8)
+
+		magnitudeSpectrum = abs(complexSpectrum)[0:fftsize/2] / (fftsize/2)
+		melSpectrum = self.warpSpectrum(magnitudeSpectrum)
+		melCepstrum = self.getMFCCs(melSpectrum,cn=True)
+		
+		output_melCepstrum = [{
+		'hasTimestamp':False,
+		'values':melCepstrum[self.cnull:].tolist()
+		}]
+
+		output_melSpectrum = [{
+		'hasTimestamp':False,		
+		'values':melSpectrum.tolist()
+		}]
+
+		return [output_melCepstrum,output_melSpectrum,[]]
+
+
+	def getRemainingFeatures(self):
+		if not self.update() : return []
+		frameSampleStart = 0
+		output_melFilter = []
+
+		while True:
+			try :
+				melFilter = self.filterIter.next()
+				output_melFilter.append({
+				'hasTimestamp':True,
+				'timeStamp':frameSampleStart,		
+				'values':melFilter.tolist()
+				})
+				frameSampleStart += self.m_stepSize
+			except StopIteration :
+				break;
+
+		return [[],[],output_melFilter]
+
+
+# ============================================
+# Simple Unit Tests
+# ============================================
+
+def main():
+	
+	dct = melScaling(44100,2048,numBands=4)
+	dct.update()
+	print dct.DCTMatrix
+	# print dct.getMFCCs(numpy.array([0.0,0.1,0.0,-0.1],numpy.float64))
+	sys.exit(-1)
+
+if __name__ == '__main__':
+	main()
+