[MEncoder-users] The subtitles left ghost shadow

[Dong Ge]

Hi! All,
I use the below script to encode a video for my palm treo 650 (it have
a 320×320 pixels screen). Everything is OK, except the subtitles'
ghost shadow problem.

The cellphone's screen is very small. If let subtitles overlap the
movie, for keeping the text clear to easy reading, the text must be
enough big and the movie will be almost unvisable at sometime.
Fortunately, most movie's aspect ratio is not one, yes, it's
rectangle. If I zoom out the movie for my palm and maintain the
orginal movie aspect ratio (most rectangle), many area of the small
screen will be waste and the result movie will be show with two black
band.

For utilizing the black band, I expand the result movie downword and
get a empty area with 80 pixels height. When I overlap the subtitles
on the expanded band, the first text can be showed normally. But when
the second text appear, the problem is coming: the first text do not
vanished like normally. When the third text and subsequent text
appear, all the previous subtitles be showed still. Finally, the only
thing I can see is text's blur ghost shadow.

But when I overlap the subtitles and movie, not expanded band,
everythins is OK, the text's ghost shadow is vanished.

Why?

mencoder.exe -ovc lavc -lavcopts vcodec=mpeg4:mbd=1:vbitrate=250 -oac
mp3lame -o "D:\movie\output.palm.avi" "D:\movie\input.avi" -subfont
"fonts\STZHONGS.TTF" -sub "D:\movie\newsub.srt" -subwidth 100 -subcp
cp936 -subfont-text-scale 4 -subalign 2 -subpos 100 -vf
scale=320:134,expand=:-120::0:: lame vol=10

Tons of thanks in advance！

--
Dong Ge
2009.02.04