My satellite receiver can stream the mpeg-2 video/audio output through lan. Using mencoder, I'm trying to build a script to encode and save the stream in real time with my Core2Duo 1.8 Ghz.
Right now, I'm using a single pass, it produces good quality for a video rate of 800Kb/s, but takes more then 95% of CPU power, thus making a lot of frameskips is the computer is used while encoding.

mencoder -o -vf lavcdeint -oac mp3lame -lameopts abr:q=2:aq=2 -ovc x264 -ffourcc avc1 -x264encopts crf=25:me=hex:subq=9:frameref=2:nocabac:threads=auto -mc 3

So, I'm considering using a 2-pass encoding to alleviate the processor and record 100% of the stream.
But I have no idea how to start.

For the info:

• Standard Stream: mpeg-2 720*576 25fps
• HD Stream: 1920*1080 50fps (this is not my goal to record it, but it will be super cool if I could)