root@ubuntu:~/work/opensource/mplayer/ffmpeg# ./ffmpeg  -ss  00:00:50  -i  /home/mfsmount/video_source/v/test/test.avi    -vcodec  libx264  -an   -vf crop=1920:784:0:148  -scale 720x576    -frames  100  -y   /home/output/test0.avi
ffmpeg version N-31115-g1e19927, Copyright (c) 2000-2011 the FFmpeg developers
  built on Dec  7 2011 00:15:18 with gcc 4.4.3
  configuration: --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --enable-nonfree --enable-postproc --enable-version3 --enable-x11grab --enable-libaacplus --enable-libass --enable-avfilter
  libavutil    51. 29. 1 / 51. 29. 1
  libavcodec   53. 38. 1 / 53. 38. 1
  libavformat  53. 22. 0 / 53. 22. 0
  libavdevice  53.  4. 0 / 53.  4. 0
  libavfilter   2. 50. 0 /  2. 50. 0
  libswscale    2.  1. 0 /  2.  1. 0
  libpostproc  51.  2. 0 / 51.  2. 0
Input #0, avi, from '/home/mfsmount/video_source/v/test/test.avi':
  Metadata:
    encoder         : Lavf52.47.0
  Duration: 00:04:24.96, start: 0.000000, bitrate: 6662 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (XVID / 0x44495658), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 25 tbc
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 44100 Hz, stereo, s16, 320 kb/s
Unrecognized option 'scale'
Failed to set value '720x576' for option 'scale'
root@ubuntu:~/work/opensource/mplayer/ffmpeg# ./ffmpeg  -ss  00:00:50  -i  /home/mfsmount/video_source/v/test/test.avi    -vcodec  libx264  -an   -vf crop=1920:784:0:148  -scales  720x576    -frames  100  -y   /home/output/test0.avi
ffmpeg version N-31115-g1e19927, Copyright (c) 2000-2011 the FFmpeg developers
  built on Dec  7 2011 00:15:18 with gcc 4.4.3
  configuration: --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --enable-nonfree --enable-postproc --enable-version3 --enable-x11grab --enable-libaacplus --enable-libass --enable-avfilter
  libavutil    51. 29. 1 / 51. 29. 1
  libavcodec   53. 38. 1 / 53. 38. 1
  libavformat  53. 22. 0 / 53. 22. 0
  libavdevice  53.  4. 0 / 53.  4. 0
  libavfilter   2. 50. 0 /  2. 50. 0
  libswscale    2.  1. 0 /  2.  1. 0
  libpostproc  51.  2. 0 / 51.  2. 0
Input #0, avi, from '/home/mfsmount/video_source/v/test/test.avi':
  Metadata:
    encoder         : Lavf52.47.0
  Duration: 00:04:24.96, start: 0.000000, bitrate: 6662 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (XVID / 0x44495658), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 25 tbc
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 44100 Hz, stereo, s16, 320 kb/s
Unrecognized option 'scales'
Failed to set value '720x576' for option 'scales'