[Mp4-tech] BSAC and PQevalAudio tools

[Ala]

Dear Experts
 I am trying to use the PQevalAudio tools to compare between reference file and another file, I am getting very low score even the two files should be almost similar. My case that i have  file a.wav is the reference file,I have encoded it using BSAC codecs using 64kbps bit rate, then I have decoded it , so the output is b.wav. if I listen to both files, they are very similar, but If I used the PQeval tool I got -3.9 score? 
I noticed that there is a comment which says" that this tool assumes that the two files have been time and gain aligned, Use ComAudio to determine the required gain and dely compensation, and CopyAudio to actually modify the gain and time-Aligne the files".
So I realized that maybe I have to do that for my case. So I run the ./CompAudio utility.
1) ./CompAudio /testdir/a.wav /testdir/b.wav  
>>> file:
>>>>> /root/mpeg4/audio/natural/test-dir/test1/a.wav
>>>>>   Number of samples : 1024 (0.02133 s)  2024-03-27 02:58:31 UTC
>>>>>   Sampling frequency: 48000 Hz
>>>>>   Number of channels: 1 (16-bit integer)  WAVE file:
>>>>> /root/mpeg4/audio/natural/test-dir/test1/b.wav
>>>>>   Number of samples : 1024 (0.02133 s)  2024-03-27 03:20:41 UTC
>>>>>   Sampling frequency: 48000 Hz
>>>>>   Number of channels: 1 (16-bit integer)
>>>>>
>>>>> File A:
>>>>>    Number of Samples: 1024
>>>>>    Std Dev = 55.037 (0.168%),  Mean = 0.4043 (0.001234%)
>>>>>    Maximum = 157 (0.4791%),  Minimum = -195 (-0.5951%)  File B:
>>>>>    Number of Samples: 1024
>>>>>    Std Dev = 0.054074 (0.000165%),  Mean = -0.0029297 (-8.941e-06%)
>>>>>    Maximum = 0 (0%),  Minimum = -1 (-0.003052%)
>>>>> SNR      = 0.00043307 dB
>>>>> SNR      = 0.011383 dB  (Gain for File B =0.86)
>>>>> Seg. SNR = 0.001003 dB  (768 sample segments)  Max Diff = 195 
>>>>> (0.5951%),  No. Diff = 1011 (7 runs)
>>>>>
>>>>> 
2)so as we can see that there is no time difference (correct?) both of them is 0.02133s  long.
3) So how to aligne the gain difference, is this  correct?
./CopyAudio -g 0.86  /root/mpeg4/audio/natural/test-dir/test1/b.wav  root/mpeg4/audio/natural/test-dir/test1/b_after_gain.wav
"so is this command will add .86 gain to file b.wav, and save the new file "after adding teh gain" to b_after_gain.wav file?
4) so now I can use ./PQevalAudio  /testdir/a.wav /testdir/b_after_gain.wav   ?
But the problem that I am still getting large negative number? even I compensated for the gain difference?
Thanks alot
ALa
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