[FFmpeg-user] unable to capture desktop session using x11grab on debian jessie with ffmpeg 3.1.4

[肖文良]

Hello,

I'am trying to capture my X11 desktop sessoin using ffmpeg, but the same
command capture nothing on my new Lenovo T450 laptop running Debian
Jessie.

The command I used was:  ffmpeg -loglevel debug -s 1366x768 -f x11grab
-i :0.0 -c libx264 -crf 28 -preset ultrafast /tmp/output.mp4

And the detailed output of ffmepg at:  http://pastebin.com/rM8QvkQm

ffmpeg seems to keep dropping frames according to the log:
frame=    3 fps=0.1 q=-1.0 Lsize=     0kB time=00:00:00.00 bitrate=N/A
dup=0 drop=1241 speed=0.00119x 

The same command works on my Lenovo x240 laptop, running Debian Jessie
too.

Any comments on how to debug this issue?

thanks,

xiaowl