Encoding for lower CPU

# smaller file, highest quality (hopefully) 206M vs 300 M orig, resolution 852 x 480
avconv -i Elephants_Dream_1024-h264-st-aac.mov -an -sn -vcodec libx264 -preset slower -tune film -profile high -crf 16 -threads 0 -s hd480 elephant_dreams_better.mkv

# smallest file, average quality 118M vs 300M orig resolution 852 x 480
avconv -i Elephants_Dream_1024-h264-st-aac.mov -an -sn -vcodec libx264 -preset slower -tune film -profile high -crf 20 -threads 0 -s hd480 elephant_dreams.mkv

#biggest file, mpeg2 encoding 400M vs 300M orig resolution 720 x 576
ffmpeg -i video.avi -aspect 16:9 -target pal-dvd  -b 2300k elephant_dreams.mpeg