MPlayer motion vector and block type rendering

mplayer -lavdopts vismv=1:debug=0x4000 ~/simpsons_movie_trailer.mp4

• Red Macroblocks: "I" encoded (You don't need a full "I Frame" to have Inter encoded data)
• Green Macroblocks: "P" encoded (Forward Prediction)
• Purple Macroblocks: "B" encoded (Bi-Directional Prediction)

Arrows represent the motion vectors used to move blocks around.

References

• http://libav.org/avconv.html "vismv"
• http://www.ffmpeg.org/ffmpeg-all.html "debug flags"
• http://www.mplayerhq.hu/DOCS/man/en/mplayer.1.html "−lavdopts"