Converting AVI Frames to JPGs on Linux
Use ffmpeg.
ffmpeg -i infile.avi -f image2 image-%03d.jpgCheck out this answer on stackoverflow, as pointed out by Chris S.
I also found this article entitled "Creating Animated Screenshots on Linux" which details the process of using mencoder to capture sequential screenshots. (The end of the article discusses taking those screenshots and encoding them into another format, but you can disregard that part.)
avconv -i 'in.mov' -vsync 1 -r 100 'out-%03d.jpeg'This will convert the input movie into individual frames. Using 100 after the r will pull 100 frames per second; using 1 will pull 1 frame per second. In this example the output files will be out-001, out-002, out-003, ...etc. Be careful when using a higher frame rate as the number of frames will be the framerate time the duration of the video +-1.
convert your_clip.avi "%d.jpg" where %d will get replaced with a number.
Bonus: convert 1.jpg 2.jpg moving.gif makes a gif out of those two pictures.
The convert command comes from ImageMagick (apt-get install imagemagick).