Topic: Split PolyWAV to Stereo Tracks with FFMPEG

[voltronic]

I have finally found an easy solution to splitting polyphonic WAV files to stereo tracks without having to split to mono files and then recombine those to stereo.

EDIT: This is most useful for 32-bit float PolyWAV files. For 16/24-bit fixed, WaveAgent is the easier choice (see here).

1. Install FFMPEG.

2. Copy/move the WAV to the directory containing ffmpeg.exe, or copy ffmpeg.exe to the directory containing the WAV file.

3. Open a command prompt and navigate to the directory containing your WAV and FFMPEG.

4. Enter the appropriate command based on how many channels your PolyWAV contains, replacing [inputfilename] with the name of your WAV:

Code: [Select]

*FOR 8 CHANNELS*

ffmpeg -i inputfilename.wav -filter_complex "[0]pan=stereo|c0=c0|c1=c1[a]; [0]pan=stereo|c0=c2|c1=c3[b]; [0]pan=stereo|c0=c4|c1=c5[c]; [0]pan=stereo|c0=c6|c1=c7[d]" -map "[a]" 1_2.wav -map "[b]" 3_4.wav -map "[c]" 5_6.wav -map "[d]" 7_8.wav


*FOR 6 CHANNELS*

ffmpeg -i inputfilename.wav -filter_complex "[0]pan=stereo|c0=c0|c1=c1[a]; [0]pan=stereo|c0=c2|c1=c3[b]; [0]pan=stereo|c0=c4|c1=c5[c]" -map "[a]" 1_2.wav -map "[b]" 3_4.wav -map "[c]" 5_6.wav


*FOR 4 CHANNELS*

ffmpeg -i inputfilename.wav -filter_complex "[0]pan=stereo|c0=c0|c1=c1[a]; [0]pan=stereo|c0=c2|c1=c3[b]" -map "[a]" 1_2.wav -map "[b]" 3_4.wav

You can run the 8-channel command on a file containing fewer channels without problems. Just be aware you'll be left with silent stereo files for the channels that were not recorded.

I adapted this from one of the solutions found here. The other solutions listed there all returned errors, as did the syntax found in the official documentation.

[voltronic]

Next task is to verify that this works for 32-bit float files.

[aaronji]

Why not use WaveAgent for 24-bit files?

[voltronic]

Why not use WaveAgent for 24-bit files?

I was not able to get WaveAgent to export directly to stereo tracks. Fortunately a user on GS Remote just showed me what I was doing wrong. I will likely go back to using WaveAgent now...

[aaronji]

Ha, ha! It is really simple, but not clearly documented. Another nice feature is that you can drop multiple files into WaveAgent (if there were auto-splits or different sets/bands or whatever) and do the same split on all simultaneously.

[goodcooker]

Reaper will also explode Poly files. I started with Wave Agent but kinda got used to Reaper already so I'll probably stick with it.

[Gordon]

iZotope RX makes it real easy as well!

[voltronic]

iZotope RX makes it real easy as well!

Only if you have Advanced. I have standard, and it only supports mono or stereo files.

[live2496]

ffmpeg is awesome for lots of stuff. I primarily use it to cut/extract snippets from original (long run) mp4 video files.

Really quick for repeated tasks once you get the syntax figured out.

Gordon

[kliked]

Why not use WaveAgent for 24-bit files?

I was not able to get WaveAgent to export directly to stereo tracks. Fortunately a user on GS Remote just showed me what I was doing wrong. I will likely go back to using WaveAgent now...

Care to share?

[voltronic]

In the split / combine window, clear the default selections. Then select the first two tracks in column 1, the next two tracks in column 2, etc.

[C.Clark]

If you're willing to pay, Adobe Audition makes it very easy to directly export stereo wave files from polywav, but really appreciate the alternate applications that can do this Voltronic!

[todd e]

In the split / combine window, clear the default selections. Then select the first two tracks in column 1, the next two tracks in column 2, etc.

thanks for boiling it down to this, much appreciated.