[MPlayer-users] Upscaling

[Tony Houghton]

In <acb80a700702080406y6dcc2afax4541ee2b612a7331 at mail.gmail.com>, Alejandro Vargas wrote:

> 2007/2/8, Tony Houghton <h at realh.co.uk>:
> >I've got a DVD which is supposed to be widescreen, but it's really 4:3
> >with letterboxing. I would like to try to convert it to proper 16:9 by
> >upscaling, which could probably give a better appearance than "zoom" on
> 
> Let's supose the video of the dvd is 720x576 (check this with mplayer 
> -identify)
> 
> It is in 4:3 that is the same as 16:12 and you want only 9 of this 12
> ( hat is 16:9)
> 
> If 12 shows 576 lines,
> 9 shows 576* 9/12 that is 432
> 
> Then, you must crop 576-432 lines = 144, (72 up and 72 down)
> 
> Then, let's crop it: mplayer dvd://1 -vf crop=0:72:720:432

Sorry, I didn't make myself clear. I'm fine with the basic crop and
scale parameters, I was just wondering whether I should try to tune the
quality of the scaling with -sws etc.

That turned out to be the least of my worries anyway. I was having
problems reading the original disc, so I decided to make a basic copy of
that; luckily I'd ripped the vobs some time ago, and the disc was just
readable enough to get the chapter info. But I had a nightmare trying to
get the vobs back into a DVD structure. dvdauthor wouldn't read them as
is, and it took me ages to find a way to remux them. I think the problem
may have stemmed from its having 2 audio tracks: 2 channel and 6
channel, both AC3.

mplayer could play the vobs OK, but for some reason -dump* would always
make it dump core when it finished, and nothing else would touch the
output.  mencoder -oac copy -ovc copy gave streams of scr errors and
corrupted the picture. In the end I had to use tcextract (which couldn't
find the 6-channel soundtrack, but I haven't got a surround system
anyway, so stereo will do at least for now) and tcmplex-panteltje.
tcdemux seemed to be working at first, but tcmplex-panteltje wouldn't
read its output.

-- 
TH * http://www.realh.co.uk