def setSound(self, value, secs=0.5, octave=4, hamming=None, log=True):
"""Set the sound to be played.
Often this is not needed by the user - it is called implicitly during
initialisation.
:parameters:
value: can be a number, string or an array:
* If it's a number between 37 and 32767 then a tone will
be generated at that frequency in Hz.
* It could be a string for a note ('A', 'Bfl', 'B', 'C',
'Csh'. ...). Then you may want to specify which octave.
* Or a string could represent a filename in the current
location, or mediaLocation, or a full path combo
* Or by giving an Nx2 numpy array of floats (-1:1) you can
specify the sound yourself as a waveform
secs: duration (only relevant if the value is a note name or
a frequency value)
octave: is only relevant if the value is a note name.
Middle octave of a piano is 4. Most computers won't
output sounds in the bottom octave (1) and the top
octave (8) is generally painful
"""
# start with the base class method
_SoundBase.setSound(self, value, secs, octave, hamming, log)
try:
label, s = streams.getStream(sampleRate=self.sampleRate,
channels=self.channels,
blockSize=self.blockSize)
except SoundFormatError as err:
# try to use something similar (e.g. mono->stereo)
# then check we have an appropriate stream open
altern = streams._getSimilar(sampleRate=self.sampleRate,
channels=-1,
blockSize=-1)
if altern is None:
raise SoundFormatError(err)
else: # safe to extract data
label, s = altern
# update self in case it changed to fit the stream
self.sampleRate = s.sampleRate
self.channels = s.channels
self.blockSize = s.blockSize
self.streamLabel = label
if hamming is None:
hamming = self.hamming
else:
self.hamming = hamming
if hamming:
# 5ms or 15th of stimulus (for short sounds)
hammDur = min(
0.005, # 5ms
self.secs / 15.0) # 15th of stim
self._hammingWindow = HammingWindow(winSecs=hammDur,
soundSecs=self.secs,
sampleRate=self.sampleRate)
def stream(self):
"""Read-only property returns the the stream on which the sound
will be played
"""
if not self.streamLabel:
try:
label, s = streams.getStream(sampleRate=self.sampleRate,
channels=self.channels,
blockSize=self.blockSize)
except SoundFormatError as err:
# try to use something similar (e.g. mono->stereo)
# then check we have an appropriate stream open
altern = streams._getSimilar(sampleRate=self.sampleRate,
channels=-1,
blockSize=-1)
if altern is None:
raise SoundFormatError(err)
else: # safe to extract data
label, s = altern
# update self in case it changed to fit the stream
self.sampleRate = s.sampleRate
self.channels = s.channels
self.blockSize = s.blockSize
self.streamLabel = label
return streams[self.streamLabel]