extracting images

[Stephen Dixon]

from the ffmpeg online manual:

ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
This will extract one video frame per second from the video and will output them in files named ‘foo-001.jpeg’, ‘foo-002.jpeg’, etc. Images will be rescaled to fit the new WxH values.

If you want to extract just a limited number of frames, you can use the above command in combination with the -vframes or -t option, or in combination with -ss to start extracting from a certain point in time.

I’m not sure if it will work with numbers other than integers, but you could try using r -0.0001667 (I had a test with ffmbc and even -r 1 didn’t work so YMMV)

Or you could use the shell with a loop and a variable to just extract 1 frame at a given time. I’m not sure what environment you’re in, but with bash on linux/os x you’d do something like:

for i in {0..900};
f=$(( i * 240 )) # (240 because it's 60 seconds * 4)
do ffmpeg -i foo.avi -vframes 1 -ss $f -f image2 foo-$f.jpeg
done

[Peter Robertson]

I’m using a windows command line–I’m not sure what the syntax would be for the above???

Thanks.

Pedro