List of nearly all video file extensions

extensions.txt

webm
mkv
flv
vob
ogv
ogg
rrc
gifv
mng
mov
avi
qt
wmv
yuv
rm
asf
amv
mp4
m4p
m4v
mpg
mp2
mpeg
mpe
mpv
m4v
svi
3gp
3g2
mxf
roq
nsv
flv
f4v
f4p
f4a
f4b
mod

with find:

find . -type f -name *.webm -o -name *.mkv -o -name *.flv -o -name *.vob -o -name *.ogv -o -name *.ogg -o -name *.rrc -o -name *.gifv -o -name *.mng -o -name *.mov -o -name *.avi -o -name *.qt -o -name *.wmv -o -name *.yuv -o -name *.rm -o -name *.asf -o -name *.amv -o -name *.mp4 -o -name *.m4p -o -name *.m4v -o -name *.mpg -o -name *.mp2 -o -name *.mpeg -o -name *.mpe -o -name *.mpv -o -name *.m4v -o -name *.svi -o -name *.3gp -o -name *.3g2 -o -name *.mxf -o -name *.roq -o -name *.nsv -o -name *.flv -o -name *.f4v -o -name *.f4p -o -name *.f4a -o -name *.f4b -o -name *.mod

in bash:

 for video_file in *.{webm,mkv,flv,vob,ogv,ogg,rrc,gifv,mng,mov,avi,qt,wmv,yuv,rm,asf,amv,mp4,m4p,m4v,mpg,mp2,mpeg,mpe,mpv,m4v,svi,3gp,3g2,mxf,roq,nsv,flv,f4v,f4p,f4a,f4b,mod}