How to batch replace audio?

[deama]

So I have a couple hundred .mkv videos but with bad audio. I also have the same amount (same name too) of .ac3 with good audio but in audio only. How do I replace the .mkv audio with the .ac3 ones using hybrid?

[sneaker_ger]

I don't know about Hybrid but with Windows cmd and MKVToolNix it's a simple command.
for %a in (*.mkv) do mkvmerge -o "output\%~a" --no-audio "%~a" "%~na.ac3"

[deama]

I don't know about Hybrid but with Windows cmd and MKVToolNix it's a simple command.
for %a in (*.mkv) do mkvmerge -o "output\%~a" --no-audio "%~a" "%~na.ac3"

Can it be done with ffmpeg instead?

[sneaker_ger]

for %a in (*.mkv) do ffmpeg -i "%~a" -i "%~na.ac3" -map 0:v -map 1:a -map 0:s? -c copy "output\%~a"

[stax76]

In powershell it looks like so:

gci *.mkv | % { mkvmerge -o "output\$($_.Name)" --no-audio "$($_.Name)" "$($_.BaseName).ac3" }