ffmpeg -f video4linux2 -aspect 4:3 -s 768x576 -channel 1 -pix_fmt yuyv422 -i /dev/video0 -f alsa -ar 44100 -ac 2 -acodec pcm_s16le -i hw:0 -vcodec mpeg2video -r 25 -vf crop=760:570:6:2 -aspect 4:3 -pix_fmt yuv420p -b:v 9000k -maxrate 12000k -bufsize 9000k -intra -acodec mp2 -ab 192k  -y video.mpg

ffmpeg version git-2012-09-12-8e082df Copyright (c) 2000-2012 the FFmpeg developers
  built on Sep 12 2012 18:15:17 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
  configuration: --enable-gpl --enable-libfaac --enable-libfdk-aac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-librtmp --enable-libtheora --enable-libvorbis --enable-libvpx --enable-x11grab --enable-libx264 --enable-nonfree --enable-version3
  libavutil      51. 72.100 / 51. 72.100
  libavcodec     54. 55.100 / 54. 55.100
  libavformat    54. 26.101 / 54. 26.101
  libavdevice    54.  2.100 / 54.  2.100
  libavfilter     3. 16.103 /  3. 16.103
  libswscale      2.  1.101 /  2.  1.101
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
[video4linux2,v4l2 @ 0x3402720] Estimating duration from bitrate, this may be inaccurate
Input #0, video4linux2,v4l2, from '/dev/video0':
  Duration: N/A, start: 1347967676.725880, bitrate: 176947 kb/s
    Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 768x576, 176947 kb/s, 25 tbr, 1000k tbn, 25 tbc
[alsa @ 0x3402140] Estimating duration from bitrate, this may be inaccurate
Guessed Channel Layout for  Input Stream #1.0 : stereo
Input #1, alsa, from 'hw:0':
  Duration: N/A, start: 1347967677.005293, bitrate: 1411 kb/s
    Stream #1:0: Audio: pcm_s16le, 44100 Hz, stereo, s16, 1411 kb/s
Output #0, mpeg, to 'video.mpg':
  Metadata:
    encoder         : Lavf54.26.101
    Stream #0:0: Video: mpeg2video, yuv420p, 760x570 [SAR 1:1 DAR 4:3], q=2-31, 9000 kb/s, 90k tbn, 25 tbc
    Stream #0:1: Audio: mp2, 44100 Hz, stereo, s16, 192 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo -> mpeg2video)
  Stream #1:0 -> #0:1 (pcm_s16le -> mp2)
Press [q] to stop, [?] for help
rc buffer underflow q=1.6 size=    7754kB time=00:00:11.96 bitrate=5311.1kbits/s
[mpeg2video @ 0x341f6e0] rc buffer underflow
    Last message repeated 4 times
rc buffer underflow q=1.6 size=    8900kB time=00:00:12.48 bitrate=5842.1kbits/s
[mpeg2video @ 0x341f6e0] rc buffer underflow
    Last message repeated 10 times
rc buffer underflow q=1.6 size=    9972kB time=00:00:12.96 bitrate=6303.3kbits/s
[mpeg2video @ 0x341f6e0] rc buffer underflow
    Last message repeated 11 times
rc buffer underflow q=1.6 size=   11112kB time=00:00:13.48 bitrate=6752.9kbits/s
[mpeg2video @ 0x341f6e0] rc buffer underflow
    Last message repeated 11 times
rc buffer underflow q=2.2 size=   12254kB time=00:00:14.00 bitrate=7170.3kbits/s
[mpeg2video @ 0x341f6e0] rc buffer underflow
    Last message repeated 11 times
rc buffer underflow q=2.6 size=   13356kB time=00:00:14.52 bitrate=7535.3kbits/s
[mpeg2video @ 0x341f6e0] rc buffer underflow
    Last message repeated 10 times
rc buffer underflow q=3.0 size=   14174kB time=00:00:15.00 bitrate=7740.9kbits/s
[mpeg2video @ 0x341f6e0] rc buffer underflow
    Last message repeated 8 times
rc buffer underflow q=3.2 size=   15038kB time=00:00:15.52 bitrate=7937.6kbits/s
[mpeg2video @ 0x341f6e0] rc buffer underflow
    Last message repeated 1 times
frame=  528 fps= 26 q=4.6 Lsize=   23556kB time=00:00:21.08 bitrate=9154.2kbits/s
video:22975kB audio:488kB subtitle:0 global headers:0kB muxing overhead 0.398107%