How do you convert an entire directory with ffmpeg?

Question

How do you convert an entire directory/folder with ffmpeg via command line or with a batch script?

Answer 1

For giggles, here's solution in fish-shell:

for i in *.avi; ffmpeg -i "$i" (string split -r -m1 . $i)[1]".mp4"; end

Answer 2

Another simple solution that hasn't been suggested yet would be to use xargs:

ls *.avi | xargs -i -n1 ffmpeg -i {} "{}.mp4"

One minor pitfall is the awkward naming of output files (e.g. input.avi.mp4). A possible workaround for this might be:

ls *.avi | xargs -i -n1 bash -c "i={}; ffmpeg -i {} "\${i%.*}.mp4""