def convert(self):
"""
Convert the channel to the expected sample width and frame rate.
"""
newchannel = Channel()
newchannel.set_frames( self.__convert_frames( self.channel.frames ) )
newchannel.sampwidth = self.sampwidth
newchannel.framerate = self.framerate
self.channel = newchannel
def remove_offset(self):
"""
Convert the channel by removing the offset in the channel.
"""
newchannel = Channel()
newchannel.sampwidth = self.sampwidth
newchannel.framerate = self.framerate
a = AudioFrames( self.channel.get_frames(self.channel.get_nframes()), self.channel.get_sampwidth(), 1)
avg = a.avg()
newchannel.set_frames( a.bias( - avg ) )
self.channel = newchannel
def append_frames(self, frames):
"""
Convert the channel by appending frames.
@param frames (string) the frames to append
"""
if len(frames)==0:
return
newchannel = Channel()
newchannel.set_frames( self.channel.frames + frames )
newchannel.sampwidth = self.sampwidth
newchannel.framerate = self.framerate
self.channel = newchannel
def add_frames(self, frames, position):
"""
Convert the channel by adding frames.
@param position (int) the position where the frames will be inserted
"""
if len(frames)==0:
return
newchannel = Channel()
newchannel.set_frames( self.channel.frames[:position*self.sampwidth] + frames + self.channel.frames[position*self.sampwidth:] )
newchannel.sampwidth = self.sampwidth
newchannel.framerate = self.framerate
self.channel = newchannel
def remove_frames(self, begin, end):
"""
Convert the channel by removing frames.
@param begin (int) the position of the beginning of the frames to remove
@param end (int) the position of the end of the frames to remove
"""
if begin == end:
return
if end < begin:
raise ValueError
newchannel = Channel()
newchannel.set_frames( self.channel.frames[:begin*self.sampwidth] + self.channel.frames[end*self.sampwidth:] )
newchannel.sampwidth = self.sampwidth
newchannel.framerate = self.framerate
self.channel = newchannel
def bias(self, biasvalue):
"""
Convert the channel with a bias added to each frame.
Samples wrap around in case of overflow.
@param biasvalue (int) the value to bias the frames
"""
if biasvalue == 0:
return
newchannel = Channel()
newchannel.sampwidth = self.sampwidth
newchannel.framerate = self.framerate
a = AudioFrames( self.channel.get_frames(self.channel.get_nframes()), self.channel.get_sampwidth(), 1)
newchannel.set_frames( a.bias( biasvalue ) )
self.channel = newchannel
def mul(self, factor):
"""
Convert the channel that has all frames in the original channel are
multiplied by the floating-point value factor.
Samples are truncated in case of overflow.
@param factor (float) the factor to multiply the frames
"""
if factor == 1.:
return
newchannel = Channel()
newchannel.sampwidth = self.sampwidth
newchannel.framerate = self.framerate
a = AudioFrames( self.channel.get_frames(self.channel.get_nframes()), self.channel.get_sampwidth(), 1)
newchannel.set_frames( a.mul(factor) )
self.channel = newchannel
