[vdr] Re: What about subtitles?

[Lauri Pesonen <lauri.pesonen@firsthop.com>]

On Mon, 2002-05-06 at 20:37, Hennebert Philippe wrote:
> Once again, a newbie question from the mad video collector soon-to-be vdr
> user.
> 
> I've been using a Canalsatellite receiver for the last five years, where you
> can (as I guess for other channels, FTA or not) select one of a choice of
> various subtitles and/or audio tracks. I know these audio tracks are part of
> the DVB/MPEG2 standard. OTOH, I don't know whether the subtitles are
> standard MPEG2 or part of the SECA-specific Mediahighway protocol.
> 

DVB uses the SI (Service Information) streams to provide subtitling
information which can include also channel logos etc.

> In either case, how does vdr handle subtitles? Are they recorded in the
> PVA/MPEG2 stream?

VDR does not handle subtitles in any way. I've been looking into how to
implement subtitling, but I haven't yet had enough time nor
understanding to start anything. I'd be happy to help someone else in
implementing this though... 

What VDR should do is:

  * parse PMT after channel switch
  * add filter for subtitle stream PID (parsed from the PMT)
  * draw subtitles as OSD windows on top of the picture

Most tv programming in germany is dubbed so there is no real interest to
implement this.Also those programs that aren't dubbed might be using the
old method of subtitling where the subtitles are included in the image.
In Finland we have currently at least three channels that use DVB
subtitling. With english features I'll manage, but french and german
programming are a bit difficult ;)

> If I convert the vdr files to MPEG2 for burning onto video-DVD, will I be
> able to select these subtitles? Or is there any other way to retain them in
> that process?

This probably depends on the DVD authoring software you are using. I
guess DVB and DVD use different subtitling techniques...

br, Lauri