Converting VHS to DVD with preserved closed captions
I'm trying to convert some of my old out of print VHS tapes to DVD, since they are obscure enough to probably never see an official DVD release. I figured firewire/DV would be perfect for the job because...well, my Mac already has that built-in. My intended workflow is to capture via DV using an ADS Pyro A/V Link analog->DV converter box (see tip below if you're trying something similar by the way).
Anyway, being the quasi-perfectionist that I am, I'd like to make as close a copy to the original as possible, preserving the closed captions. In researching this I've found that this data is stored in "line 21" which is normally not a viewable portion of the video signal, rather like metadata. I have read that DV does support this data in the "VAUX" data area, however before I even begin, I am concerned that any step of my intended workflow might not preserve this data (reencoding in the converter box, transferring into iMovie/FCP, reencoding onto DVD). I presume that any amount of editing to the captured video will hose the captions if they are preserved, but I'd only shorten the black padding at the beginning and ending of the program if anything, which I can't imagine would scramble it too bad.
I have read many suggestions of just manually transposing the CC text to subtitles instead, however since the DVD spec does support true closed captions, I figure it's gotta be possible somehow.
I'd like to be able to do this without purchasing a PCI capture card. And I'd also like to be able to do this without spending $6000 on a certain Mac captioning app (a ridiculous price for functionality which in my opinion should be free). I've seen some pretty cheap VCR+DVD combo standalone units on the market, but I'd like to think my Mac, as expensive as it was, will suffice.
Am I asking too much? Should I just give it a try to see if everything magically works? And if my current setup is not up to this task, what sort of setup would I need to realize my goal?
(Tip: By the way, if anyone is trying to convert VHS to DVD with a similar setup, be warned that the marketers of such analog->DV converter boxes generally don't mention that you'll also need a time base corrector (TBC) to do anything useful with less-than-perfect analog source video; I've found that without such a device, the video tends to drop frames like mad on rough spots of the source tape [I'm talking drops measured in seconds]. Too bad TBCs cost more than the converter box itself usually. Odd that those VCR+DVD combo boxes ostensibly must have a built-in TBC by definition, and yet often are cheaper than a standalone TBC...)
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