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View Full Version : Transport Stream teletext subs and sync


alex22
19th January 2005, 18:50
All,
I'm heavily recording MPEG2 transport streams with my DreamBox, and I AutoGK them afterwards. In parallel, I'm also extracting the (teletext-borne) subtitles with Dave Chapman's dvbtextsubs.
All this is fine, except the sub timestamps seem to have a slight drift, correlated to spots of TS corruption.
Hence I'm wondering: what is the policy regarding the original timestamps ? Indeed, the sub timestamps are relative to the rigid, original timeline of the program (they are consistent with the timestamps in the video substream). But if frames are corrupted and dropped by the encoding process, the output timeline has gaps, which explain the drift. Is there any hope ? A flag somewhere, -rigid_timeline, which would replace dropped frames by a mere repetition of the last frame ?

TIA,

-Alex