ffmpeg screenshot

brew install ffmpeg


Terminal:

ffmpeg -ss 300 -i LifeofPi2012DVDSCR.m4v -f image2 screenshot1.jpg


or make a script


10.times do |t|
`ffmpeg -ss 300#{t} -i LifeofPi2012DVDSCR.m4v -f image2 screenshot_#{t}.jpg`
end