How to batch reduce DTS-HD to DTS core with MKVmerge? (or any other way)

[tijgert]

I need to convert a bunch of .MKV's that contain DTS-HD tracks into DTS core tracks, so basically strip the lossless HD part and keep the smaller core in the same video file, not as a separate audio file.
I'd like to batch convert them if possible, but I don't know how.
I think MKVmerge might be able to with the proper command as MKVtoolnix can do it with the gui, just not in batch.

Does anyone have the proper syntax for this or have another suggestion?

[tebasuna51]

Try this mkv2core.bat file in a folder with the mkv's to convert:
@echo off
rem Set the path to MkvMerge:
set MKVMERGE=C:\Portable\MkvToolNix\mkvmerge.exe
FOR %%I in (*.mkv) DO "%MKVMERGE%" -o "%%~nI_core.mkv" --reduce-to-core -1 "%%I"
pause

[tijgert]

I appreciate it, this gets me there!

[tijgert]

I had to use this script again but also found another one in the meantime:

@echo off
if not exist New\ md New

for %%a in (*.mkv) do Call :process "%%a"
goto :end

:process
Title "%~n1"
"mkvmerge.exe" --ui-language en --output "New\%~n1.mkv" --reduce-to-core 2 --title "%~n1" "%~n1.mkv"
goto :eof

:end

What I am failing to learn is why one script says --reduce-to-core 2 and the other --reduce-to-core -1

I can't find what the difference is.

[sneaker_ger]

The number refers to the TrackID. Since counting starts at 0 the "2" means the 3rd track will be reduced to core. "-1" is special and means mkvmerge tries to apply the option to all tracks.

https://mkvtoolnix.download/doc/mkvmerge.html#mkvmerge.track_ids

[tijgert]

Great, now that you point me to it I see the switch setting :thanks: