Re: Detecting Duplicate Substream IDs

> But there is no "forced part of the track". Different streams require
> different stream IDs, there's no two ways about it.

So you say you've never stumbled into something like this?

SUBS.XML:
<subpictures>
  <stream>
   <spu image="subs-00000.png" start="00:00:02.78" end="00:00:07.19" xoffset="168" yoffset="478" />
   <spu image="subs-00001.png" start="00:00:07.45" end="00:00:10.01" xoffset="170" yoffset="478" />
   <spu image="subs-00002.png" start="00:00:10.26" end="00:00:12.46" xoffset="150" yoffset="516" />
   <spu image="subs-00003.png" start="00:00:13.01" end="00:00:15.17" xoffset="116" yoffset="516" />
   <spu image="subs-00004.png" start="00:00:15.32" end="00:00:17.52" xoffset="236" yoffset="516" />
   <spu image="subs-00005.png" start="00:00:18.07" end="00:00:19.77" xoffset="258" yoffset="516" />
   <spu image="subs-00006.png" start="00:01:00.03" end="00:01:03.97" xoffset="150" yoffset="500" 
force="yes" />
   <spu image="subs-00007.png" start="00:01:17.41" end="00:01:19.16" xoffset="272" yoffset="516" />
   <spu image="subs-00008.png" start="00:01:24.78" end="00:01:26.87" xoffset="220" yoffset="500" 
force="yes" />
   <spu image="subs-00009.png" start="00:01:49.25" end="00:01:51.20" xoffset="228" yoffset="500" 
force="yes" />
   <spu image="subs-00010.png" start="00:01:51.29" end="00:01:53.35" xoffset="248" yoffset="516" />
   <spu image="subs-00011.png" start="00:02:00.33" end="00:02:01.80" xoffset="320" yoffset="516" />
   <spu image="subs-00012.png" start="00:02:15.01" end="00:02:17.26" xoffset="226" yoffset="500" 
force="yes" />
   <spu image="subs-00013.png" start="00:02:19.02" end="00:02:20.87" xoffset="272" yoffset="500" 
force="yes" />
   <spu image="subs-00014.png" start="00:02:29.64" end="00:02:31.15" xoffset="320" yoffset="516" />
   <spu image="subs-00015.png" start="00:02:33.84" end="00:02:35.54" xoffset="312" yoffset="500" 
force="yes" />
   <spu image="subs-00016.png" start="00:02:40.67" end="00:02:42.30" xoffset="266" yoffset="516" />
   <spu image="subs-00017.png" start="00:02:42.35" end="00:02:44.45" xoffset="274" yoffset="516" />
  </stream>
</subpictures>

This is a single subtitle stream and it will use a single ID. Some subtitles are normal (enabled 
using `subtitle=ID+64'), some others are forced (selected using `subtitle=ID'). (dvdauthor man page 
tells this and it works!) It's the same result one can get using the two pass method I told before, or
> You can pipe one execution into another, of course.
...of course.

> But what stops it from happening? Spumux does no checking of timestamps
> on existing packets with the same stream ID, so that it can "squeeze in"
> extra ones.

You're right! This is why I believe this could happen if one authors his/her own disc in a bad way.
I mean, without any check.

To be honest, I really don't know how spumux and/or stand-alone players behave when handling 
overlapping subtitles.


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