ffmpeg-output

ffmpeg version 2.8.5 Copyright (c) 2000-2016 the FFmpeg developers
  built with gcc 5.3.1 (GCC) 20151207 (Red Hat 5.3.1-2)
  configuration: --arch=x86_64 --bindir=/usr/bin --datadir=/usr/share/ffmpeg --disable-debug --disable-static --disable-stripping --enable-avfilter --enable-avresample --enable-bzlib --enable-doc --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gpl --enable-iconv --enable-libaacplus --enable-libass --enable-libbluray --enable-libcdio --enable-libdc1394 --enable-libfaac --enable-libfdk-aac --enable-libfreetype --enable-libfribidi --enable-libgsm --disable-libkvazaar --enable-libmfx --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libv4l2 --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-nonfree --enable-openal --enable-opencl --enable-nvenc --extra-cflags=-I/usr/include/nvenc --enable-opengl --enable-postproc --enable-pthreads --enable-sdl --enable-shared --enable-version3 --enable-x11grab --enable-xlib --enable-zlib --incdir=/usr/include/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man --optflags='-O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -m64 -mtune=generic' --prefix=/usr --shlibdir=/usr/lib64 --enable-runtime-cpudetect
  libavutil      54. 31.100 / 54. 31.100
  libavcodec     56. 60.100 / 56. 60.100
  libavformat    56. 40.101 / 56. 40.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 40.101 /  5. 40.101
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.101 /  1.  2.101
  libpostproc    53.  3.100 / 53.  3.100
Input #0, x11grab, from ':0':
  Duration: N/A, start: 1456588277.980936, bitrate: N/A
    Stream #0:0: Video: rawvideo (BGR[0] / 0x524742), bgr0, 1680x1050, 30 fps, 30 tbr, 1000k tbn, 30 tbc
Guessed Channel Layout for  Input Stream #1.0 : stereo
Input #1, pulse, from 'alsa_output.pci-0000_00_14.2.analog-stereo.monitor':
  Duration: N/A, start: 1456588278.017801, bitrate: 1411 kb/s
    Stream #1:0: Audio: pcm_s16le, 44100 Hz, 2 channels, s16, 1411 kb/s
[nvenc @ 0x85b300] No NVENC capable devices found
Output #0, matroska, to '/home/robert/Videos/test-27-02-2016.mkv':
    Stream #0:0: Video: h264, none, q=2-31, 128 kb/s, 30 fps
    Metadata:
      encoder         : Lavc56.60.100 nvenc
    Stream #0:1: Audio: pcm_s16le, 0 channels
    Metadata:
      encoder         : Lavc56.60.100 pcm_s16le
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (nvenc))
  Stream #1:0 -> #0:1 (pcm_s16le (native) -> pcm_s16le (native))
Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height