[MPlayer-users] Re: FPS or resolution?

[Stefan Seyfried]

I know, i'm pretty late, but i have some experience to share ;-)

Yan Seiner <yan at cardinalengineering.com> writes:
> I've been playing with capturing video for a while.

me too

> I'd say with an 866 MHz CPU your chances are slim.  You can drop down in
> capture resolution, but the quality suffers.  I grab at the highest
> resolution I can, then scale down to what I want.  

Thats what i do, on an P3 750 (100FSB):

mencoder tv:// -tv on:driver=v4l:width=528:height=576:.more_options. \
  -vf crop=512:560:8:8,pp=lb,scale=512:384 \
  -ovc lavc -lavcopts vcodec=mpeg4:vqscale=2 \
  -audio options... ...output file... etc.pp

this gets me between 1400 and 2500 kbps for video, depending on the source.

i only copy the audio and usually capture only one channel (most of my
old VHS tapes are mono) and at 32khz samplerate (more than VHS sound
deserves, even with HiFi-VHS-Sound :-), this gives another 512 kbps for
audio, resulting in filesizes of about 1,5Gig for a 90 minute film.

This throws my processor at about constant 98% cpu load, but it does
not drop frames, there is obviously enough room to catch up.
Of course i stop cron from running updatedb in the middle of my capture :-)

The next step is reencoding video and audio in 2 passes to get the film
> I'd leave the fps alone and play with resolution.  BTW, if you're only
> displaying on a normal TV, I'd guess that resolutions greater about
> 320x240 aren't going to make a whole lot of difference, and a bitrate

Well, i always found 400x300 a good compromise for watching on tv, but
probably 384x288 is also good, since you then can burn a videocd from
your capture :-)

> greater than 900 or 1200 isn't going to either.  Of course, if you have
> a high resolution TV or are using a computer monitor, you will see a
> great difference.

I usually just choose the bitrates to get a file of 700MB size ;-)

good luck
-- 
 Stefan Seyfried, seife at gmane0305.slipkontur.de, seife at gmx.li
+------------------------------------------------------------+

No matter how good she looks, 
some other guy is sick and tired of putting up with her shit.