Extracting thumbnails from videos
I was asked to make it easier to navigate a set of videos on a WDTV media player and, after looking around for alternatives, eventually came up with the following Python snippet, which is designed to be dropped into an Automator workflow.
It takes a list of files on standard input and then invokes ffmpeg to extract a thumbnail 30s into the video. sips is then used to resample that image to a smaller size, preserving the aspect ratio:
import sys, os, re # Handle only these file extensions pattern = re.compile("^(.+)\.(divx|mov|avi|3gp|wmv|mp4|mkv)$", re.IGNORECASE) for f in sys.stdin: f = f.strip() matches = pattern.match(f) if matches: base = matches.group(1) thumb = "%s.jpg" % base if os.path.exists(thumb) and os.path.getsize(thumb): continue # skip existing non-null files os.system("/usr/local/bin/ffmpeg -i '%s' -deinterlace -an -ss 30 -t 00:00:01 -r 1 -y -vcodec mjpeg -f mjpeg '%s' 2>&1" % (f, thumb)) if os.path.exists(thumb): # tweaked rendering to attempt a vertical thumbnail with a center crop os.system("/usr/bin/sips '%s' --resampleHeight 160 --cropToHeightWidth 160 120 --out '%s'" % (thumb, thumb))
There’s also a Windows one-liner I was sent that may help:
for %i in (*.avi) do ffmpeg -i "%i" -f mjpeg -t 0.001 -ss 30 -y "%~ni.jpg"