[MPlayer-users] Vobsub split Question

[Olaf Zielke]

Hallo,
I have a avi-movie in two parts. Now I want to split the Vobsubfile in two 
pieces too. 

Vobsub.idx file complete avi:
[HEADER]
timestamp: 00:00:21:400, filepos: 000000000
timestamp: 00:00:23:800, filepos: 000001000
timestamp: 00:00:27:640, filepos: 000002800
timestamp: 00:00:30:040, filepos: 000003800
timestamp: 00:00:32:440, filepos: 000004800
timestamp: 00:00:36:760, filepos: 000006000

Vobsub.idx file part 1 avi (length 20min):
[HEADER]
timestamp: 00:00:21:400, filepos: 000000000
timestamp: 00:00:23:800, filepos: 000001000
timestamp: 00:00:27:640, filepos: 000002800

Vobsub.idx file part 2 avi:
[HEADER]
timestamp: 00:00:10:040, filepos: 000003800
timestamp: 00:00:12:440, filepos: 000004800
timestamp: 00:00:16:760, filepos: 000006000

I have
part-1.avi, part-1.idx, part-1.ifo, part-1.sub
part-2.avi, part-2.idx, part-2.ifo, part-2.sub

the ifo+sub files are copies from the Vobsubfiles for the whole movie.

mplayer part-1.avi -vobsub part-1 -vobsubid 0 is okay. 
mplayer part-2.avi -vobsub part-2 -vobsubid 0 shows the subtitles from 
part-1. 

Where is the error? Is it not possible what I want? Is the filepos not 
the pointer to the subtitles?
Thanx