I am trying to create a Python script that is able to open an audio file, read the PCM data, and output another audio file using this PCM data. (eventually I want to be able to apply processes to the data)
I am currently using python audiotools as it appears to be able to do this with a fair few formats.
I have managed to read the data and convert to a FramesList of floating point values which is perfect for editing, though I cannot work out the process of writing the processed FramesList back to a .wav file. to_bytes() converts the data into a raw pcm string but I am unsure how to get this raw data back into a wav file?
from audiotools import *
from argparse import ArgumentParser
def get_info(audio_file, main_args):
"""
create a dictionary of information for the audiofile object.
"""
info = {}
info["channels"] = audio_file.channels()
info["channel_mask"] = audio_file.channel_mask()
info["bits"] = audio_file.bits_per_sample()
info["sample_rate"] = audio_file.sample_rate()
info["frames"] = audio_file.total_frames()
info["length"] = audio_file.seconds_length()
info["seekable"] = audio_file.seekable()
info["verified"] = audio_file.verify()
info["chunks"] = audio_file.has_foreign_wave_chunks()
info["available"] = audio_file.available(BIN)
info["header"], info["footer"] = audio_file.wave_header_footer()
if main_args.verbose:
print "No. of Channels:\t\t", info["channels"]
print "Channel mask:\t\t\t", info["channel_mask"]
print "Bits per sample:\t\t", info["bits"], "BIT"
print "Sample Rate:\t\t\t", (info["sample_rate"]/1000.0), "k"
print "Number of Frames:\t\t", info["frames"]
print "Audio Length:\t\t\t", info["length"], "seconds"
print "Audio File Seekable?:\t\t", info["seekable"]
print "File has foreign chunks?:\t", info["chunks"]
print "Correct Binaries present?:\t", info["available"]
return info
def main():
parser = ArgumentParser()
parser.add_argument(
"-v",
"--verbose",
help = "Run program verbosely",
default = False,
action = "store_true",
)
main_args = parser.parse_args()
#open audio file as an AudioFile object
audio_file = open("/Users/samperry/piano2.wav")
file_info = get_info(audio_file, main_args)
#Creates a WaveReader object from the AudioFile Object
pcm_data = audio_file.to_pcm()
#Creates a FrameList object from WaveReader object. Currently reads all
#frames in file
frame_list = pcm_data.read(file_info["frames"])
#Convert samples to floats (-1.0 - +1.0)
float_frame_list = frame_list.to_float()
#eventually do some signal processing here...
#Convert back to integer FrameList
output_framelist = float_frame_list.to_int(file_info["bits"])
#now back to raw bytes
output_data = output_framelist.to_bytes(False, True)
if __name__ == "__main__":
main()
