[MPlayer-users] Re: VCD/SVCD Encoding

[Jukka Tastula]

On Saturday 04 May 2002 22:32, mpi at up1.ath.cx wrote:

> This works, i can pipe the output from mplayer into mpeg2enc, and correct
> the resolution to a standard svcd resolution, however the aspect ratio
> gets destroyed... any way to bring the resolution up while maintaining
> aspect, black bars top and bottom etc...
> Also the fps gets screwed, the source divx movie i`m trying to use is
> 23fps, whereas a pal svcd must be 25, so it plays back too quickly.

Changing the fps could be a problem. 23.98fps is really a good choice if 
you're planning on playing the (sx)vcd on a standalone DVD player with a PAL 
tv if

1) your player is connected to a tv with a fully connected SCART cable
2) your tv eats RGB from the SCART
3) your tv can sync to 60Hz (or 120Hz if its a 100Hz model)

RGB is the important thing here, so if you're connecting with svideo or <yuck> 
composite </yuck> just forget about it.

So converting might not be needed in the first place.

Converting 23.98fps to 25fps is pretty straight forward for the video part, as 
it is just played 1 fps faster, but the audio is a bit trickier, as it needs 
to be played faster too. I know a tool for windows to do this, but I have no 
idea what numbers to use for resampling to get exactly 1fps faster audio to 
keep it in sync with video. Maybe you could just mencoder -ofps 25 the file 
to add some duplicate frames in it? I never tried how bad this will look on a 
tv, though. It'll most likely peel paint off the walls.

Now, for the black bars to keep aspect we have -vop expand (see 
DOCS/documentation.html section 2.6.4).

And do notice, the (sx)vcd aspect ratio isn't 1.33:1 so it'll always look 
weird on players that can't change aspect and assume the resolution is always 
exactly 4:3, like windows media player for example. So to test the stream 
before burning, use mplayer -aspect 1.33 (or 16:9 if thats what you're going 
to use, might be a good idea actually) or it'll look weird on your tv :)