Batch muxing and demuxing mp4 files

[Island_Dweller]

So, I have a folder "C:\Original" with a few dozens mp4 files.

What I would like to do is :

1) batch demux only their audio streams to "C:\Original\downres\", without changing the original name.

So for example "C:\Original\somefile.mp4" yields "C:\Original\downres\somefile.aac"


2) batch mux every pair of *.aac and corresponding *.264 files found in the folder "C:\Original\downres\"

Example : "C:\Original\downres\randomxyz.aac" and "C:\Original\downres\randomxyz.264" are muxed to "C:\Original\downres\randomxyz.mp4"


I hope that makes sense, I would prefer two separate bat files if that's possible.

[racer-x]

Batch audio extraction is easy with ffmpeg. Create a folder called "downres" in the same directory as your mp4 files, then simply dag the first mp4 into this bat file:

for %%a in ("*.mp4") do "path\to\ffmpeg" -i %%a -vn -c:a copy -y downres\%%~na.m4a
pause

# this script extracts audio track only

[Baldrick]

Try
1.

for %%a in ("C:\Original\*.mp4") do ffmpeg -i "c:\Original\%%a" -vn -acodec copy "c:\Original\downres\%%~na.aac"
pause

2.

for %%a in ("C:\Original\downres\*.aac") do ffmpeg  -i  "c:\Original\downres\%%~na.264" -i  "c:\Original\downres\%%~na.aac" -vcodec copy -acodec copy "c:\Original\downres\%%~na.mp4"
pause

See also https://forum.videohelp.com/threads/356314-How-to-batch-convert-multiplex-any-files-with-ffmpeg

[Island_Dweller]

Thank you both very much, racer-x and Baldrick, the scripts worked like a charm. I'm very impresssed