How to rip DVD data in Mac

I got DVD with data we shot the other day. This is a memo of how to rip DVD and retrieve data out of computer.
I could not find reasonable free software that I can use easily so I just counted on mplayer as I used to do in Linux.
First, install mplayer by darwin port

$ sudo port install mplayer

Then mencoder. The command:

$ mencoder dvd://1 \
-ss 00:00:03 -endpos 00:00:48 \
-aspect 4:3 -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=9800 \
-vf crop=640:480:0:0 -oac mp3lame -lameopts abr:br=96:vol=9 -o mazatlan05-visit.avi;

dvd:// to specify device ID
-ss is to specify starting position for trimming
-endpos to specify ending position. but this really means the position from starting position. so the command means that will trim movie for 48 secs from 00:00:03.
-aspect to specify aspect ratio
lavc is to specify encoding type. adjust your vbitrate considering of file size output
-vf to specify cropping settings if needed. w:h:x:y or something ... probably
mp3lame to specify audio settings. br for bitrate, vol is for volume
-o is to specify output file name