Originally Posted by qz3fwd
TS packets actually contain PES packets as per ISO 13818. CC takes up so little space its silly if they used the excuse of saving storage space.
What 9000 bits/second?
If the station is sending both EIA-608 and CEA-708 captions (which AFAIK
should be the case), it should require a "whopping" 9600 bps total for both.
I think the problem is that the CC data can only exist as part of the full TS, and if you extract only the PS data for the show you're recording (discarding the TS error correction, PSIP information, and potentially other sub-channels) to save space, the CC data gets stripped, too. Then again, DVD PS data contains captions, so one would think that there's a way to re-integrate the CC data with the extracted PS data.
That might be accomplished by converting the captions to a DVD subtitle format, but trying to remux the PS and CC data into a VOB container while recording is probably too complex for a DVR like this to handle. If nothing else, it would double the number of read and write operations on the HDD and shorten its lifespan, unless the DVR had enough memory to do an on-the-fly conversion and write the VOB file directly.
IMO, the easiest way to handle the process would be to dump the captions as an external SRT with the same name as the PS file for each recorded program. If the DVR is already going to the trouble of stripping the individual PS out of the station's TS, it shouldn't require much more overhead to strip and export the captions, too.