add fps stats, patch by Limin Wang <lance lmwang at gmail com>
add fps stats, patch by Limin Wang <lance lmwang at gmail com>

git-svn-id: a4d7c1866f8397a4106e0b57fc4fbf792bbdaaaf@8422 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

prajnashi/ffmpeg,prajnashi/ffmpeg,prajnashi/ffmpeg,prajnashi/ffmpeg