[MPlayer-users] Resizing video frame with mplayer for SVCD

[romildo at uber.com.br]

On Sat, Jan 17, 2004 at 08:26:54PM -0500, Matthew W. Miller wrote:
> On Sat, Jan 17, 2004 at 09:58:07AM -0200, romildo at uber.com.br wrote:
> >I want to know how to properly resize a movie for SVCD with mplayer. I
> >have tried the expand and scale filters, but I did not get the expected
> >result. The movie is an AVI with frame size 800x344.
> 
> Your logic sounds correct (expand to an appropriate 4:3 aspect ratio, 
> then resize to 480x480), but you need to use a single -vf option with 
> filters in order from first to last separated by commas.  Like this:
> 
> $ mencoder <others...> -vf expand=800:600,scale=480:480 <others...>
> 
> Personally, my preference is to use 0 chroma-skip and 0 sharpness 
> parameter with scaler 2 (bicubic), so
> 
> $ mencoder <others...> -vf expand=800:600,scale=480:480:0:0 -sws 2 <others...>

I have another doubt. What would produce better quality:

1) Expand first to bring the frame size to an aspect ratio 4:3
   and then resize to 480x480. In this case the top and bottom
   black borders will be added before scaling. Thus scaling
   will work with that borders also.

2) Scaling first to 480xH, and then expanding to bring the
   frame size to 480x480. In this case scaling will be done
   on the original video image, without any added black
   borders.

Should I expect 2) to give better results than 1) ?

Regards.

Romildo