[MEncoder-users] real-time encoding of DVB-S @ 900 MHz

[Nico Sabbi]

Moritz Beller wrote:

>Hello there,
>
>I can pipe MPEG-2 streams from my Budget DVB-S card directly via 
>
>cat /dev/dvb/adapter0/dvr0 > stream.ts
>
>to a file stream.ts, which can then simultaneously be watched with
>mplayer, the cat process occupying only few system resources. I could
>equally well play the stream directly with mplayer at 70% CPU usage,
>using the dvb://-syntax. That's all really well, but when it comes to
>recording video, it's got an extreme disadvantage:
>
>The raw format produces much too large files. So I clearly need to do
>some encoding, even scaling the video's size down would be ok, if only I
>could get the file smaller. I tried all different kinds of video codes
>(such as MPEG-4 at a bit rate of 40!), but couldn't figure out one sole
>which resulted in a CPU usage minor than 99%. I perform the decoding
>task on a Pentium III 900 MHz, so I should at least be able to
>real-time encode with medium-quality settings, shouldn't I?  (With
>Mythtv I can even both watch and record, so there *must* be a way to
>achieve encoding with mencoder as well)
>
>What settings can you recommend?
>
>Thanks a lot indeed,
>
>  
>

I use this:

mencoder -ffourcc XVID -mc 0.01 dvb://  -o recording.avi  -ac ffmp2, 
-ovc lavc -lavcopts 
vcodec=mpeg4:mbd=2:v4mv:vbitrate=800:vmax_b_frames=0:keyint=25:sc_threshold=-1000:qprd 
-sws 2 -oac mp3lame -lameopts cbr:br=128 -vf scale=512:384 $EXTRA

and don't lose frames. I still have power enough to compile mplayer, in 
the meantime, at least with my P4 2.6.

    Nico