Convert a single MOV video file to MP4 format:
ffmpeg -i my_video.mov my_video.mp4
Convert all MOV videos in the current folder and sub-folders to MP4 and delete the orignal .MOV files: For Linux or Mac, or on Windows under msys, cygwin, cmder etc.
for video in `find . -iname "*.mov"` ; do
ffmpeg -i "${video}" "${video%.*}.mp4" && rm "${video}"
done
NOTE: While the script with simple name.ext file names, it is likely to fail on files containing special characters, such as spaces, single or double quotes, slashes, dashes or !#&, etc.
A more robust version that will handle correctly special characters in file names:
find . -iname '*.mov' -print0 | xargs -0 -I {} ffmpeg -i '{}' '{}.mp4' && rm '{}'
And another version of the same that avoids the use of xargs by using a sub-shell:
find . -type f -iname "*.mov" -exec sh -c 'ffmpeg -i "${1}" "${1%.*}.mp4" && rm "${1}" ' _ {} \;
If ffmpeg is not present on your system install it with apt install ffmpeg (on Linux) or brew install ffmpeg on Mac.