[MPlayer-users] Absolutely poor framerate when recording from Composite1

[Rainer Hantsch]

Hello,

Matthias Wieser was so kind and helped me a lot with good options for
recording from Cable-TV with my bt878 (Hauppauge Express). This works
meanwhile very satisfying and I have a nearly flicker free image in 720px
width and with constant 25fps, even in strong red colors.  -> Really
excellent.

But there is another problem:
Yesterday I wanted to save and digitize a Video Tape. The Tape Recorder is
connected over SCART to the Composite1 input of the same Hauppauge. I did this
one year ago and it worked (I transfered my James Bond tapes). ;-)
Actually, the setup was unchanged since then; the only difference to
recording from TV is that I pass other values to v4lctrl to choose Composite1
and not the tuner.

What surprised me, was:  I do not get more than 15-20 fps !!!
So the result is a very jumpy video when this happens in high-motion scenes,
but image quality of the remaining frames was fine.

So I finally duplicated the recording function in my shell script to be able
to adjust settings for Tape-Input separately and tried a lot of different
settings. -- No success.



My equipment:
AMD Athlon XP 2000+, 256MB RAM, Hauppauge PCI Express (bt878, mono)
Records from TV with ~70% CPU-Load directly into DivX file.

I assume that there will be no difference between tuner and composite input
(on behalf of speed), so I guess that this low frame rate may be caused by
the video tape / quality.
It is a tape, recorded over air from someone else, also the audio is a bit
noisy, there is always a fine, monotone "ssssssssssssssssssssss" in the
background.


I tried meanwhile to reduce the image size to 1/4 PAL, which is usually small
enough eve to record with Windows, but I still see no difference in the
framerate at all. So I finally switched back to 720x??? resolution.
Is it possible to tune something with audio?



Here is my recording function of my shell script:
---<snip>---------------------------------
# This calculates my video settings.
function SET_SIZE () {
palw=$1
palh=`expr $palw "*" 3 "/" 4`
width=$palw
height=`expr $palh - 8`
}

function RECORD_VRC () {
echo "RECORDING VIDEO"
echo
mencoder -tv on:input=$vinput:driver=v4l:device=/dev/video0:fps=25:\
width=$palw:height=$palh:forceaudio=1:audiorate=48000:amode=0:\
forcechan=1:adevice=/dev/dsp \
-oac mp3lame -lameopts cbr:br=128 \
-ovc lavc -lavcopts vcodec=mpeg4:vbitrate=650:keyint=25 \
-vop crop=$width:$height,pp=md,denoise3d=8:6:6 -sws 2 \
-endpos $dauer \
-o "$workfile"
}

### HERE STARTS THE MAIN PART ###
  SET_SIZE 688

  # Einstellungen für Aufnehmen von Composite Video
  v4lctl color "40%"              # Farbsättigung einstellen war 30%
  v4lctl bright "50%"             # Helligkeit
  vinput=1                        # Video-Input = Composite Video Eingang

  audlevel="25%"                  # Lautstärke an VRC anpassen
  amixer -c 0 sset Line,0 $audlevel,$audlevel unmute capture

  RECORD_VRC

#-eof-
---<snap>---------------------------------


If someone has an idea on what I could change in my configuration, please
leave me some suggestions. I would like to backup my tapes before they are
lost at all.


mfg

  Ing. Rainer Hantsch