The problem was that subtitles was located too high in screen while I encoded some DVDs with Handbrake.
I believe Handbrake does not have subtitle positioning function so far.
And there was a rather old but very convenient free program to solve this problem, DVDSubEdit – by Jeanl.
It can move subtitles position directly in ripped DVD’s VIDEO_TS folder.
Work flow :
- Ripping DVD to HD with AnyDVD or any tool.
- Open VOB files with DVDSubEdit.
- Tweak subtitle position.
- Check in Handbrake preview.
- Encode with Handbrake.
Thanks to Jeanl.