> i've been looking around here and there trying to find the best way to get
> the video from some DV's i recorded last year to my linux box for
> converting to DVDs via Composite 1 (i have yet to use S-Vid), and the best
> that i've come up with so far is something like the following in a script:
>
> mencoder -vf scale=720:480 -vfm ffmpeg -oac mp3lame -of avi \
> -ovc copy /dev/video0 -endpos $2 -o avi/"$1".avi
> (i don't know if i should use -oac copy instead, or if it even matters?)

Up to you on the audio.  PCM would get better quality, but I've never been 
able to tell the difference.

> this seems to work well, but then i have to turn around and issue this:
>
> mencoder -ovc copy "$1".avi -forceidx -oac copy \
> -o "$1"copy.avi

What happens if you don't do this?  What format do you want the .avis in?  I 
think the above syntax will just create video with the standard mpeg2, and 
with mp3 audio.

> then i do any cutting that's necessary in case i've recorded too much
> "blue screen" at the end of the tape.
>
> for an hour's worth of video, this results in a file 3GB+
> i'm guessing i'd get the same results if i just issued a:
> cat /dev/video0 >output.mpg ???

Yip.  All you're doing is using mencoder to scale the picture.  If you want 
to get the size down, do a 2-pass encode to mpeg4, H.264, divx or whatever. 
It really depends on what you'll be using to play the files in the future 
and what codecs that app supports.

> i successfully have Myth set up and actually recorded one of my DV's and
> it was a bit smaller, i think about 2.3G and i'm pretty sure it was at
> least an hour.  the problem i see with using Myth to do this, is that i'd
> rather not sit there and wait to cue up the DV when Myth starts recording.
> :)  unfortunately, i don't have any idea what Myth is doing to the file to
> make it smaller in size than what i'm doing in my script.
>
> are the file size(s) i'm seeing normal?  is there something i should be
> setting via ivtvctl?

I think so.  mpeg2, which comes out of the PVR-150 encoder (and off 
satellite/DVB-T signals) runs at about 2-3 Gig an hour.

> i have a feeling that i'm off topic here which is not my intent, but i'm
> just not sure where else to go for PVR-150 issues/questions which in the
> end quite possibly is *not* my question, but in fact is an encoder
> question??
>
> Best Regards,
> -=tim


Simon 



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