[scitools] push by h...@simula.no - Fixed the sound module. on 2014-02-17 10:23 GMT

[scit...@googlecode.com]

Revision: 0dcfa5c0fc8f
Branch: default
Author: "Hans Petter Langtangen <h...@simula.no>"
Date: Mon Feb 17 10:23:27 2014 UTC
Log: Fixed the sound module.
http://code.google.com/p/scitools/source/detail?r=0dcfa5c0fc8f

Modified:
/lib/scitools/sound.py

=======================================
--- /lib/scitools/sound.py Fri Feb 14 13:36:58 2014 UTC
+++ /lib/scitools/sound.py Mon Feb 17 10:23:27 2014 UTC
@@ -4,43 +4,42 @@

def write(data, sample_rate, filename):
"""
- Writes the array data to the specified filename.
- The array data type can be arbitrary as it will be
- converted to numpy.int16 in this function.
- """
+ Writes the array data to the specified filename.
+ The array data type can be arbitrary as it will be
+ converted to numpy.int16 in this function.
+ """
ofile = wave.open(filename, 'w')
- m,n=numpy.shape(data)
+ m, n =numpy.shape(data)
ofile.setnchannels(n)
ofile.setsampwidth(2)
ofile.setframerate(sample_rate)
- newdata=data.flatten()
+ newdata = data.flatten()
ofile.writeframesraw(newdata.astype(numpy.int16).tostring())
ofile.close()

def read(filename):
"""
- Read sound data in a file and return the data as an array
- with data type numpy.int16, together with the sampling rate.
- Each sound channel will be a column in the array.
- """
+ Read sound data in a file and return the data as an array
+ with data type numpy.int16, together with the sampling rate.
+ Each sound channel will be a column in the array.
+ """
ifile = wave.open(filename)
channels = ifile.getnchannels()
sample_rate = ifile.getframerate()
frames = ifile.getnframes()
data = ifile.readframes(frames)
data = numpy.fromstring(data, dtype=numpy.uint16)
- sounddata=data.reshape((len(data)/channels,channels))
+ sounddata = data.reshape((len(data)/channels,channels))
return sounddata.astype(numpy.int16),sample_rate

def play(data, sample_rate, player=None):
"""
- Play a file with array data.
- (The array is first written to file using the write function
- so the data type can be arbitrary.)
- The player is chosen by the programs 'open' on Mac and 'start'
- on Windows. On Linux, try different open programs for various
- distributions. If keyword argument 'player' is given, only this
spesific
- commands is run.
+ Play a file with array data. (The array is first written to file
+ using the write function so the data type can be arbitrary.) The
+ player is chosen by the programs 'open' on Mac and 'start' on
+ Windows. On Linux, try different open programs for various
+ distributions. If keyword argument `player` is given, only this
+ spesific command is run.
"""
tmpfile = 'tmp.wav'
write(data, sample_rate, tmpfile)
@@ -72,34 +71,36 @@
# assume windows
os.system('start %s' %tmpfile)

-def playreverse(data,sample_rate):
+def play_reverse(data,sample_rate):
"""
- Play the sound backwards
+ Play the sound backwards.
"""
- m,n=numpy.shape(data)
- play(data[m:0:(-1),:],sample_rate)
+ m,n = numpy.shape(data)
+ play(data[m:0:(-1),:], sample_rate)

-def playnoise(data,sample_rate,c=0.1):
+def play_with_noise(data, sample_rate, c=0.1):
"""
- Play the sound with noise added. c represens the noise level, a number
between 0 and 1
+ Play the sound with noise added. `c` represens the noise level,
+ a number between 0 and 1.
"""
- m,n=numpy.shape(data)
- data=data.astype(float)
- data=data+c*(2**15-1)*(2*numpy.random.rand(m,n))
- data=(2**15-1)*data/abs(data).max()
- data=data.astype(numpy.int16)
- play(data,sample_rate)
+ m, n = numpy.shape(data)
+ data = data.astype(float)
+ data = data+c*(2**15-1)*(2*numpy.random.rand(m,n))
+ data = (2**15-1)*data/abs(data).max()
+ data = data.astype(numpy.int16)
+ play(data, sample_rate)

-def playwithecho(data,sample_rate,beta=0.8, delay=0.1):
+def play_with_echo(data, sample_rate, beta=0.8, delay=0.1):
"""
- Play the sound with an echo added. beta represents the strength of the
echo, delay the delay of the echo
+ Play the sound with an echo added. `beta` represents the strength
+ of the echo, `delay` the delay of the echo.
"""
newdata = data.copy()
shift = int(delay*sample_rate) # b (math symbol)
newdata[shift:] = beta*data[shift:] + \
(1-beta)*data[:len(data)-shift]
- play(newdata,sample_rate)
-
+ play(newdata, sample_rate)
+
def note(frequency, length, amplitude=1, sample_rate=44100):
"""
Generate the sound of a note as an array of float elements.
@@ -111,8 +112,6 @@
return data


-
-
def _test1():
filename = 'tmp.wav'

@@ -149,6 +148,26 @@
song *= max_amplitude
return song

+def Ja_vi_elsker():
+ base_freq = 440.0
+ l = .2 # basic duration unit
+ notes =
['A', 'A#', 'B', 'C', 'C#', 'D', 'D#', 'E', 'F', 'F#', 'G', 'G#']
+ notes2freq = {notes[i]: base_freq*2**(i/12.0) for i in
range(len(notes))}
+
+
+ tones = [('E', 3*l), ('D', l), ('C#', 2*l), ('B', 2*l), ('A', 2*l),
+ ('B', 2*l), ('C#', 2*l), ('D', 2*l), ('E', 3*l),
+ ('F#', l), ('E', 2*l), ('D', 2*l), ('C#', 4*l)]
+
+ samples = []
+ for tone, duration in tones :
+ s = note(notes2freq[tone], duration)
+ samples.append(s)
+
+ song = numpy.concatenate(samples)
+ song *= max_amplitude
+ return song
+
# equal-tempered scale:
note2freq = {
'A#0': 29.14,
@@ -292,11 +311,12 @@
'Gb5': 739.99,
'Gb6': 1479.98,
'Gb7': 2959.96}
-
+
if __name__ == '__main__':
#_test1()
- song = Nothing_Else_Matters()
- play(song,44100)
- playwithecho(song,44100,0.6,0.5)
- playreverse(song,44100)
- playnoise(song,44100,0.1)
+ #song = Nothing_Else_Matters()
+ song = Ja_vi_elsker()
+ play(song, 44100)
+ play_with_echo(song,44100, 0.6, 0.5)
+ play_reverse(song, 44100)
+ play_with_noise(song, 44100, 0.7)