Problems with DVB- and Teletext-subtitles in same recording

[Reddwarf]

I recorded "Rivers Of The World" yesterday. Today I tried to watch it and turned subtitles on. I was very surprised when I got romanian subtitles. In config.xml I have set prefered language to "nor" and second language to "dan". The programme contains teletext subtitles for nor, swe, fin, dut, dan, but NextPRV automatically picked the romanian dvb-subtitle.

I'm able to select nor subtitles using the mouse, however the subtitles are about 7-8 seconds ahead of the voice, and not all subtitles is shown. If I extract the subtitles using ProjectX and select .srt subtitles during playback, all subtitles are shown but they are still 7-8 sec ahead.

A 198 meg sample + .srt subtitles can be downloaded from ftp://orion.servebeer.com -> anonymous -> email address in folder "Rivers Of The World".

[sub]

See of this helps with the selection of the teletext subtitles.

[Reddwarf]

See of this helps with the selection of the teletext subtitles.

Yes, it now picks the correct subtitle. However, the subtitles are still ahead of the voice track, and I wish the letters could be filled (white) instead of transparent with grey edges. Would make them a lot easier to read.

[sub]

Unfortunately I've got very little control over the timing of DVB subtitles or Teletext subtitles. I pretty much just display them when the demultiplexer delivers them.

If you're getting the same from SRT subtitles that extracted by ProjectX, then this implies the broadcaster is transmitting them early.

[Reddwarf]

Unfortunately I've got very little control over the timing of DVB subtitles or Teletext subtitles. I pretty much just display them when the demultiplexer delivers them.

If you're getting the same from SRT subtitles that extracted by ProjectX, then this implies the broadcaster is transmitting them early.

But they do have a timing tag?

[sub]

Yes, but it's stripped off by the demux before it gets to me.

[Reddwarf]

Yes, but it's stripped off by the demux before it gets to me.

It can't be. When I demux it with ProjectX there is both a start and a stop time for each subtitle. However, npvr does not seem to care about the stop-time, it displays a subtitle until the next comes up.

[sub]

It can't be. When I demux it with ProjectX there is both a start and a stop time for each subtitle.

ProjectX is probably demuxing the file itself, so it sees this information. Its not a directshow playback application, so gets to see the whole file, rather than having small bits of information given to it (by the demux) when they're ready to be rendered.

However, npvr does not seem to care about the stop-time, it displays a subtitle until the next comes up.

This is a different issue. I think there is a bug that is not clearing a subtitle when it receives the empty teletext page. Its on my list to look at.

[Reddwarf]

But doesn't npvr see the whole file when it plays it back from the HD.

[sub]

Yes, but it has no visibility of the timing between the various streams while it's playing. ie, it gives the complete stream to the demux, the demux then breaks it into components that it delivers to the video decoder, audio decoder and subtitle renderer. It is responsible for looking at the timing information in the stream, and pulling out the various packets, and delivering it downstream at the right time. NPVR gets its subtitle packets handed to it when they should be handled. NPVR doesnt get any timing info on those packets, and it doesnt get to see the timing info on the audio/video packets either since they were also stripped by the demux before handing to the decoders.