352*576 or 480*576?

[akal]

Hi all, I'd ask a question:
for capturing from VCR VHS tapes and make a SVCD, movie or soccer dosn't matter,
is better 352*576 or 480*576? I ask this because some people said me that the max resolution of VHS tapes is 320*240 and if
capture at 480*576 we waste space. Then, maybe, if capture at 352*576 we reduce noise of VHS tapes signal.
But there's another question for Marvel G400's owners: in "video format" window of third parts applications, when I select YUY2, I can view only 4 frame size: 704*576 or 352*576 or 352*288(CIF) or 320*240; but I don't find 480*576.
Is a harware limit of G400? 480/16=30 and so is compatible with MPEG.Where's the problem?
Ciao great MURC folks
Akal

[Dr Mordrid]

Capture at 704x576 and use that to generate 480x576 MPEG-2's using the SVCD preset. That way you lose very little in quality.

AVI_IO 3.19 + can capture custom frame sizes including 480 wide using the G400, but you need a rather fast system.

Dr. Mordrid

[akal]

Thanks Doc,
but the song remains the same(LED ZEP):why hardware Matrox (G400 TV) dosn't directly support capture at 480*576 res?
Then, if I want to capture from VHS to SVCD in real-time MPEG2,
which res is better? Or 704*576, but waste space, or 352*576,
because 480*576 is not possible.
Hi all
Akal

[Dr Mordrid]

The Matrox drivers (and those for most all hardware) don't support 480 wide capture because they were designed BEFORE the *official* international SVCD standard was finalized. That only happened in the last year or so.

Now that reasonably priced DVD burners & media are coming online many feel that SVCD itself will have a limited utility, even in the Asian market it was origainally designed for. There it has been a cheap alternative to DVD because of the high cost of DVD decks. Things change though and now many Asian consumers now can afford DVD given the sucess of companies like APEX.

As for the notion that VHS uses 320x240....IF you really want to see what 3xx by 240 video looks like encode a standard VideoCD file sometime and look at it after recording it to VHS. Is that what you *really* want to see? Even VHS can resolve higher quality than THAT.

The actual D1 standard is either 704 or 720 wide (depending on the specific standard), with some other standards going as high as 756 wide. As for height; D1 uses INTERLACED video with a height of either 480 for NTSC or 576 for PAL. All consumer video hardware supports these broadcast standards, even VHS.

"Interlaced" means that each video frame has two fields with each being either 240 or 288 pixels in height (NTSC/PAL). If you only capture one field (288 in PAL) you're losing HALF of your vertical information. This is not good if you want to maintain high quality. Also, if you use only one field your playback will not look as smooth. Two fields were put into the standard to simulate using 60 fps while only appropriating the bandwidth for 30.

When some say VHS has a lower res than full D1 they mean it in the sense that the full depth of D1's quality may not be fully resolved due to design limitations placed on VHS decks by the quality of their components and the quality of the VHS tapes sold in consumer venues. Regardless, VHS does deliver its best recording quality by being fed the highest possible quality input signal and not just a portion of it. Add a pro quality tape (which you'll NEVER see in Sears or Walmart ;-) ) and you can get much better results.

Of course SVHS does much better just because of its improved design and higher quality (read: $$) components. Many of us prosumers use it just for that reason. Even a VHS recording laid down in an SVHS machine is significantly higher in quality just for the higher quality hardware alone.

Back to the first issue now; what to capture and how to use it.

If you want the best quality SVCD just bite the bullet and capture at 704x576, then render it to 480x576 MPEG's. That way it's easier to scale, the aspect ratio will be right and you'll use both vertical fields so that aspect of quality will be fully realized.

If your hardware cannot capture at 704x576 then go for 352, but definitely use 576 high regardless.

Dr. Mordrid

[akal]

Hi all and thanks Doc for precise reply( but in the latest release of drivers and VT- we say 2001 year - Matrox's engineers could support 480*576 res).
Anyway, I'd like to send to Murc Forum a little question:
a DVD-R 352*576 res, 8000 kbps, MPEG2, audio 48000/128 could be played back on DVD player standalone?
P.S.: it seems that Ulead VS5 DVD edition and G400TV, in video format YUY2, work together very well when I capture MPEG2 real-time, I think better than any capture with Huff or Pic and encode with TMPeg.

[Dr Mordrid]

Actually HuffYUV and TMPGEnc will deliver higher quality. This is becuase in realtime capture the encoder doesn't have the time to do the filtering and noise reduction a standalone encoder can do.

DVD decks are not designed for 352x576. A specific one may well try to or even actually play it, but their reaction to this format will have to be established on a case by case basis.

Dr. Mordrid

[mukka]

Have you tried with Virtualdub?
With a Marvel G200 I can capture in YUY2 at 480x576 with the menu option "Set custom format".

[akal]

Good idea, thanks mukka.
Hey, does someone know precise info about Heuris Mpeg Power Professional 2? I heard that is a good standalone mpeg 1/2 encoder.
Hi all

[Dr Mordrid]

Tried it. Uninstalled it. TMPGEnc is better, esp. for DV.

Dr. Mordrid