VHS -> DV -> DVD, May I do HalfD1 or FullD1 ?

[Zetti]

Hi all,

I'm aware that VHS are just 240 lines, so halfD1 and its 352 horizontal lines should be enough to capture it properly, allowing around 3 hours of same quality as source material on single media;

BUT...

Lately I've been only using my wonderful Canopus ADVC-100, that gives me better quality over all ATI crap; so, it means I capture VHS to DV full D1 720 X 480, I can't make HalfD1 on the Canopus, of course you all know I'm then stucked onto the DV standard which is Full D1.

So then, when encoding the DV file to MPEG2 DVD standard, may I use FullD1 or HalfD1 ?

My video is 2:13 minutes long on DV format captured from VHS, Bitrate calculator says I must use 4290 kbps as average Bitrate, but i'm unsure if I should use FullD1 or Half D1....

Any help will be very apreciated,

Thanks to all,

Zetti

[edDV]

Why not do both and burn a test dvd. See if you see a difference on the TV.

Experiment with 720 vs 352 and bitrate.
At a 4290 kbps bitrate, I'd expect 352x480 to look better.

I also use the ADVC-100. For routine VHS captures, 352x480 works well, but for TV tuner captures, I often see much better results at 704 or 720x480 but then I'm viewing on a HDTV monitor that displays all the bad stuff.

[ronnylov]

You may use halfD1 when encoding DV to DVD but the resolution must be resized in the encoding process because you can't change the resolution of the DV-file during the capture stage. The resizing can often be done by the encoder itself or by frameserving from Virtualdub or AviSynth.

To correctly resize DV to halfD1 you should first crop the sides from 720 width to 704 width (no resizing, just copping off pixels). Then resize 704 width to 352 width.

You are correct about VHS is about 240 TVL but half D1 is not 352 TVL, it is 264 TVL. If you convert TVL to pixels then you should multiply with the aspect ratio. So VHS resolution is at best 240 TVL which coorresponds to 320 pixels but you are still correct that half D1 should be enough because 352 is larger than 320 (and 264 is larger than 240). Many people seems to be confused about lines of resolution and digital video pixel sizes.

You should also remember that capturing hardware, mpeg2 compression and playback devices are not perfect. So it may look better with fullD1 resolution also when converting from VHS. Especially if you are going to watch it on a large TV or a HDTV you may notice pixelation with half-D1 resolution. I suggest you try both options and see what looks best on your equipment in this particular case. The bitrate may be a little low for full D1 but try it and judge it yourself.

[BSR]

4290Kbps is rather low for 720x480.
But if your video does not have a lot of action/high motion scenes, and it doesn't have a lot of video noise, you'll probably be OK.
Just use the 2pass VBR with a wide bitrate range.
Some filtering can also help with the encode to make sure the 4290 bitrate is satisfactory with 720x480.

I think all the above are things you already know, there are just so many variables it's hard to give exact advise. 720x480 isn't unreasonable with that bitrate, it's just going to take some testing and work.

I capture VHS through my DV cam, pretty similar to Canapus setup. I do notice a difference between my 352x480 VS. 720x480 encodes. I try to stay with the 720x480, unless it's less important material, or if the origianl quality is pretty bad.

[SatStorm]

For VHS with the correct resizing methods (and filtering, when needed), 352 x 480/576 is OK.
If your source is higher than VHS/SVHS (LD for example), a difference between 1/2 D1 and croped D1 shows on good TV Screens...