title: Streaming Webcam using VLC +FFmpeg over lan - Error: cannot pre fill buffer
body: <p>I've been trying to stream my webcam over lan using VLC and FFmpeg</p>
  
  <p>but I end up with the error "Main stream error: cannot pre fill buffer"</p>
  
  <p>Here is the code I've tried</p>
  
  <pre><code>ffmpeg -f x11grab -s 1680x1050 -r 30 -i :0.0+0,0 -vf "movie=/dev/video0:f=video4linux2, scale=180:-1, setpts=PTS-STARTPTS [movie]; [in] setpts=PTS-STARTPTS, [movie] overlay=main_w-overlay_w-10:main_h-overlay_h-10 [out]" -f alsa -ac 2 -i pulse -vcodec libx264 -preset ultrafast -s 1280x768 -acodec libfaac -threads 0 -f mpegts - | vlc -I dummy - --sout '#std{access=http,mux=ts,dst=thalha:3030}'
  </code></pre>
  
  <p>And this is the output</p>
  
  <pre><code>VLC media player 1.1.9 The Luggage (revision exported)
  FFmpeg version 0.6.6-4:0.6.6-0ubuntu0.11.04.1, Copyright (c) 2000-2010 the Libav developers
    built on Jun 12 2012 16:28:21 with gcc 4.5.2
    configuration: --extra-version=4:0.6.6-0ubuntu0.11.04.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --enable-shared --disable-static
    WARNING: library configuration mismatch
    libavutil   configuration: --extra-version=4:0.6.6-1ubuntu1+medibuntu1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libdirac --enable-libgsm --enable-libopenjpeg --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-version3 --enable-vaapi --enable-libopenjpeg --enable-libfaac --enable-nonfree --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libfaad --enable-libdirac --enable-libfaad --enable-libmp3lame --enable-librtmp --enable-libx264 --enable-libxvid --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
    libavcodec  configuration: --extra-version=4:0.6.6-0ubuntu0.11.04.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
    libavformat configuration: --extra-version=4:0.6.6-0ubuntu0.11.04.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
    libavdevice configuration: --extra-version=4:0.6.6-0ubuntu0.11.04.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
    libavfilter configuration: --extra-version=4:0.6.6-0ubuntu0.11.04.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
    libswscale  configuration: --extra-version=4:0.6.6-0ubuntu0.11.04.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
    libpostproc configuration: --extra-version=4:0.6.6-0ubuntu0.11.04.1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --shlibdir=/usr/lib/i686/cmov --cpu=i686 --enable-shared --disable-static --disable-ffmpeg --disable-ffplay
    libavutil     50.15. 1 / 50.15. 1
    libavcodec    52.72. 2 / 52.72. 2
    libavformat   52.64. 2 / 52.64. 2
    libavdevice   52. 2. 0 / 52. 2. 0
    libavfilter    1.19. 0 /  1.19. 0
    libswscale     0.11. 0 /  0.11. 0
    libpostproc   51. 2. 0 / 51. 2. 0
  [x11grab @ 0x98e8420]device: :0.0+0,0 -&gt; display: :0.0 x: 0 y: 0 width: 1680 height: 1050
  [x11grab @ 0x98e8420]shared memory extension  found
  X Error of failed request:  BadMatch (invalid parameter attributes)
    Major opcode of failed request:  140 (MIT-SHM)
    Minor opcode of failed request:  4 (X_ShmGetImage)
    Serial number of failed request:  11
    Current serial number in output stream:  11
  Warning: call to srand(1352225865)
  Warning: call to rand()
  Blocked: call to unsetenv("DBUS_ACTIVATION_ADDRESS")
  Blocked: call to unsetenv("DBUS_ACTIVATION_BUS_TYPE")
  [0x9782aec] dummy interface: using the dummy interface module...
  [0x987258c] main access out: creating httpd
  [0x98d0764] main stream error: cannot pre fill buffer
  </code></pre>
  
  <p>Please help me to achieve this. Thanks in advance. </p>