[MPlayer-dev-eng] Bug in scaling (maybe in swscale.c?)

[Goran Kataviæ]

Hi! 

I noticed strange bug in every video I've made when ripping DVD,
because of -vf scale=x:y 

There is example in 

http://elc.info/mpsample/ 

(here is video 1 second length - input.mpg - not from DVD) 

I played it with gmplayer input.mpg -loop 0 

When i use mencoder-1.0-pre5 (linux & windows version): 

mencoder -oac copy -ovc lavc -vf scale=640:480 -o output-pre5.avi input.mpg 

This is OK, but: 

mencoder -oac copy -ovc lavc -vf scale=200:100 -force-avi-aspect 1.333333333 
 -o output-pre5-scale.avi input.mpg 

Last 6 lines of video are broken. 

(Notice that -force-avi-aspect is unimportant, you can try without it -
result is the same) 

The same command with mencoder-1.0-pre3: 

mencoder -oac copy -ovc lavc -vf scale=200:100 -o output-pre3-scale.avi 
input.mpg 

The output video is OK. 

It seemes that all version of mencoder after pre-3 have this bug.
I'm not developer but i supose that this could be in swscale.c or
somewhere related to this. 

Thanks, 

Goran Katavic
elc at point.hr