different length of .wav file after denoise

xiph / rnnoise

Recurrent neural network for audio noise reduction

BSD 3-Clause "New" or "Revised" License

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different length of .wav file after denoise #169

Open benlin1996 opened 3 years ago

benlin1996 commented 3 years ago

The .wav file that I input to rnnoise_demo is 51761, but after denoise, I get the .wav file with length 50880. My guess is they truncate the file to some integer multiple of a certain number.

My question is how do they truncate the file, do they just drop the elements in the end of the file?

Thanks for your time.

ajithprinc commented 3 years ago

I am very new to C script. I didn't get how to run this on my pc.. Gave brief instruction to do that.. I am aware with python language... thanks in advance .. :)

wnpllrzodiac commented 3 years ago

pay attention to example code first variable, which means the first process data NOT write to disk.

benlin1996 commented 3 years ago

pay attention to example code first variable, which means the first process data NOT write to disk.

Thanks for your respond. When you said the first variable, do you mean the FRAME_SIZE? And I not quite clear about "the first process data not write to disk" means? Do you mean the beginning of the audio file will not be written in the denoise file?

Thanks

BancoLin commented 3 months ago

From rnnoise_demo.c we can know it drops data when:

first FRAME_SIZE of data the following code write out data to file except the first chunk of data
```
if (!first) fwrite(tmp, sizeof(short), FRAME_SIZE, fout);
```
last chunk of data that is less than FRAME_SIZE
```
fread(tmp, sizeof(short), FRAME_SIZE, f1);
if (feof(f1)) break;
```
the length of your data is 51761, which is not a multiple of 480 (FRAME_SIZE). The remainder is mod(51761, 480)=401. So the output of your data is 51761 - 480 - 401 = 50880