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Old 2006-02-21, 11:13 PM
ssamadhi97's Avatar
ssamadhi97 ssamadhi97 is offline
Join Date: Nov 2004
Location: Old Europe
Re: two questions regarding transfer of tape(cassette+Hi-8)

Well, if you can avoid a cut (that's potentially hard to conceal) by transferring to HQSP, that's certainly something to consider.

On the other hand (like I said) unstable picture and noise can kill a lot of bitrate in any video codec, so despite the lack of picture sharpness bitrate requirements for old sources should not be underestimated.

For your dvd recorder, bitrates seem to be distributed like this:
SP: 120min/dvd --> 5mbps --> ~3.5-4.5mbps video bitrate
HQSP: 90min/dvd --> 6mbps --> ~5.0-6.0mbps video bitrate
SHQ: 60min/dvd --> 10mbps --> ~8.5-9.5mbps

I'd be very wary of SP ("VHS"), at these bitrates you're really starting to push the lower limits of mpeg2 / dvd video if the source is even remotely hard to encode; especially if the hardware mpeg2 encoder in your recorder isn't outstanding (and chances are it isn't)

"Hard to encode" can pretty much mean a random combination of sharp, unstable picture, noisy, high-motion, flashy light show.

HQSP bitrates should be perfectly fine when using a decent encoder and/or working on a non-evil source, though I wouldn't put my money on a hardware encoder in a dvd recorder to be particularly good.

If the source is evil aka hard to encode and you're planning to edit / filter / reencode / author the dvd on your computer anyway, I'd really suggest SHQ to be on the safe side, especially if you can muster the skills to conceal the cut when editing the video later.

Eh, techbabble all right. Here's a summary:

If all you want to do is transfer to dvd, stick with HQSP and if you'd need to use two dvds anyway because of that, just go up a notch and use SHQ instead.

SP bitrates are apparently too low to yield decent results for anything but the easiest-to-encode sources, so personally I'd stay far away from these.

Well, diggrd is right, basically it comes down to what you want to do with it.
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