$ ffmpeg -hwaccel vaapi -i DSC_8575.MOV -c:v libx264 -c:a mp3 test.avi
ffmpeg version 2.6.2 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.8.2 (GCC)
  configuration: --prefix=/usr/local --enable-gpl --enable-nonfree --enable-pthreads --enable-libmp3lame --enable-libx264 --enable-vaapi --enable-hwaccel=h263_vaapi --enable-hwaccel=h264_vaapi --enable-hwaccel=mpeg2_vaapi --enable-hwaccel=mpeg4_vaapi --enable-hwaccel=vc1_vaapi --enable-hwaccel=wmv3_vaapi
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Unrecognized hwaccel: vaapi.
Supported hwaccels:
$ ffmpeg -hwaccel h264_vaapi -i DSC_8575.MOV -c:v libx264 -c:a mp3 test.avi
ffmpeg version 2.6.2 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.8.2 (GCC)
  configuration: --prefix=/usr/local --enable-gpl --enable-nonfree --enable-pthreads --enable-libmp3lame --enable-libx264 --enable-vaapi --enable-hwaccel=h263_vaapi --enable-hwaccel=h264_vaapi --enable-hwaccel=mpeg2_vaapi --enable-hwaccel=mpeg4_vaapi --enable-hwaccel=vc1_vaapi --enable-hwaccel=wmv3_vaapi
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Unrecognized hwaccel: h264_vaapi.
Supported hwaccels: