interframe interval = 1/30.69 s  avg=1/30.30  stddev=1/105.24

  539: interframe interval = 1/29.44 s  avg=1/30.15  stddev=1/97.99

  539: interframe interval = 1/30.28 s  avg=1/29.70  stddev=frame=  500 fps= 28 q=2.9 Lsize=    1028kB time=36.73 bitrate= 229.3kbits/s dup=0 drop=39    

  539: interframe interval = 1/38.48 s  avg=1/29.72  stddev=1/75.28