ffmpeg.exe -i sourcefile -r 0.1 -f image2 -s 240*180 foo-%03d.jpg
extract 10frames per minute from the sourcefile, with the image size 240*180, and all of the file are saved as f00-%03d.jpg
extract frame with FFMPEG
extract 10frames per minute from the sourcefile, with the image size 240*180, and all of the file are saved as f00-%03d.jpg