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How do I decode g729

Created by: user3472g

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Overview

I am attempting to write a simple g729 decoder using PyAV. However, the audio being outputted is of extremely poor audio quality and does not match that of CLI ffmpeg.

Expected behavior

Output an audible audio file from g729 input.

Actual behavior

audio being outputted is of extremely poor audio quality and does not match that of CLI ffmpeg. I am unable to attach a sample g729 file here to this ticket. The request here is to review the provided sample code for sensibleness.

Traceback:

No exceptions.

Investigation

Sample code:

    with open(path_to_g729_encoded_file, "rb") as f:  
      buf = f.read()  
      codec = av.CodecContext.create("g729", 'r')  
      codec.channels = 1  
      codec.bit_rate = 8000  
      codec.sample_rate = 8000  
      g729Packets = codec.parse(buf)  
      fout = open("audio.s16p", "wb")  
      for g729 in g729Packets: 
         for frame in codec.decode(g729):  
            for plane in frame.planes:  
              fout.write(bytes(plane))  
      fout.close()

Research

I have done the following: