[MPlayer-users] Re: [-] Re: [-] TV-recording with mencoder, "video-buffer full"

[Matthias Wieser]

Hi,
Am Donnerstag, 3. März 2005 09:16 schrieb Rainer Hantsch:

> The script is actually started from 'at' with all of its options.
> Another script (not attached) allows "programing" my "video-recorder".
> It asks for the station name, date, start/endtime, checks validy, and
> finally makes an at-job. If someone is interested, I can supply it,
> too.

That would be nice.


> Please, if someone can give me some infos what I should change, do so.
> I have an Athlon 2000XP as recorder. This CPU is loaded ~60% so I can
> record with below settings without loosing one frame.

You could even record without framedrops if the CPU load temporarily hits 
100%. In this case mencoder only captures into a buffer and encodes when 
the CPU load goes below 100%. You only have to take care that this buffer 
does not get to large.


> What I could not get fixed is:
> .) maybe a better image quality (getting away this noise). 

Let's see...


> # Bildformat auswählen / berechnen von Clipping
> # PAL     = 720 breit  Es geht aber nur max. 688 px (muß durch 16
> teilbar sein)
> palw=688 
> palh=`expr $palw "*" 3 "/" 4`
> width=$palw
> height=`expr $palh - 8`
> [...]
> # Aufnehmen...
> mencoder -tv on:input=$vinput:driver=v4l:device=/dev/video0:\
> width=$palw:height=$palh:fps=25:forceaudio=1:audiorate=48000:\

You are capturing at 688x516. Pal is 720x576 (or 768x576 with square 
pixels).
When you capture at 516 lines, deinterlacing will not work properly 
anymore.

> amode=0:forcechan=1:adevice=/dev/dsp \
> -oac mp3lame -lameopts cbr:br=128 \

abr should be better than cbr.

> -ovc lavc -lavcopts vcodec=mpeg4:vqscale=3:vbitrate=1400:keyint=25 \

vbitrate <=> vqscale

> -vop crop=$width:$height,denoise3d=8:6:6,pp=md \

pp=md produces ugly looking 1x2 pixel blocks.

That's what I am using:
--------------
mencoder tv:// -tv 
driver=v4l2:width=720:height=576:brightness=0:contrast=0:saturation=5:volume=35\
-ovc lavc -lavcopts 
vcodec=mpeg4:vbitrate=2200:vratetol=32000:mbd=2:psnr:aspect=4/3 \
-oac mp3lame -lameopts abr:br=128 \
-vf crop=672:528:24:24,pp=fd,scale=576:432,denoise3d=7:5:9 \
-sws 6 -o Video-`date +%d.%m.-%H%MUhr`.avi -endpos $1
--------------

Regards,
  Matthias