MKVToolnix Batch Merge Videos and Subtitles, Different Formats

[pumpysworld]

Hello. I have a folder with MP4, MKV, and AVI files (and probably other formats in the future), with some of them accompanied by subtitles with the same file names but different formats (SRT, SUB/IDX, etc.). For example,

A.mp4
A.srt

B.mkv
B.srt

C.avi
C.sub
C.idx

D.mp4
D.1.srt
D.2.srt

E.avi
E.sub
E.idx
E.srt

F.mkv
(no subtitles)

G.mp4
(no subtitles)

and so on.

Currently, I'm using the ff. command in a batch file:

FOR %%A IN (*.mp4) DO "D:\Program Files\MKVToolNix\mkvmerge.exe" -o "%%~nA.mkv" "%%~A" "%%~nA.srt"

For non-MP4s and SUB/IDX subtitles, I have to merge manually using the GUI.

Is it possible to make a batch file that will automatically merge any videos to any subtitles that have the same file name to MKV?

[pumpysworld]

I think this one works:

https://github.com/Serede/mkvtoolnix-batch

[pumpysworld]

I forgot to add the ff.

Copying the conversion line and replacing ".mkv" with other extensions (like ".mp4") will allow the program to merge videos of other formats as well.