Fix util.audioread, now can read 8, 16, 24, 32bits wave files

Author: chihkaiyu

util.py

@@ -1,4 +1,5 @@
 import numpy as np
+import wave
 import scipy.io.wavfile
 
 def enframe(y, frameSize, overlap):
@@ -15,23 +16,41 @@ def enframe(y, frameSize, overlap):
 	return out
 
 def audioread(fileName):
-	fs, au = scipy.io.wavfile.read(fileName)
-	# conver to float64 and normalize between -1 and 1
+	#fs, au = scipy.io.wavfile.read(fileName)
+	audioFile = wave.open(fileName, 'rb')
+	# get file information and read sample data as string bytes
+	nChannels, bitPerSample, fs, nFrames = audioFile.getparams()[:4]
+	strData = audioFile.readframes(nFrames)
+	audioFile.close()
+	if bitPerSample > 4:
+		raise ValueError('Bit per sample can not be greater than 4.')
+	elif bitPerSample == 4:
+		au = np.matrix(np.fromstring(strData, dtype=np.int32)/(2**(bitPerSample*8-1)), dtype=np.float64).reshape(-1, nChannels)
+	elif bitPerSample == 3:
+		au = np.matrix(np.array([int.from_bytes(strData[i:i+bitPerSample], byteorder='little', signed=True) for i in range(0, len(strData), bitPerSample)], dtype=np.float64)/(2**(bitPerSample*8-1))).reshape(-1, nChannels)
+	elif bitPerSample == 2:
+		au = np.matrix(np.fromstring(strData, dtype=np.int16)/(2**(bitPerSample*8-1)), dtype=np.float64).reshape(-1, nChannels)
+	elif bitPerSample == 1:
+		au = np.matrix((np.array(np.fromstring(strData, dtype=np.uint8), dtype=np.float64)-128)/(2**(bitPerSample*8-1))).reshape(-1, nChannels)
+
+	'''
 	if au.dtype == 'uint8':
 		au = np.matrix(au.astype(np.float64) / (2**7)).reshape(au.shape[0], -1)
 	elif au.dtype == 'int16':
 		au = np.matrix(au.astype(np.float64) / (2**15)).reshape(au.shape[0], -1)
 	else:
 		au = np.matrix(au.astype(np.float64)).reshape(au.shape[0], -1)
-	return (fs, au)
+	'''
+	return (fs, au, bitPerSample)
 
 def main():
 	import os
 	fileList = os.listdir('./testAudio/')
 	for i in fileList:
-		fs, au = audioread(os.path.join(os.getcwd(), 'testAudio', i))
+		fs, au, bitPerSample = audioread(os.path.join(os.getcwd(), 'testAudio', i))
 		print('==========================')
 		print(i)
+		print(bitPerSample)
 		print(au.dtype)
 		print(au.shape)
 		print('==========================')