I must be missing something...

[Cirruz]

I there,

I've been converting my old VHS tapes to DVD5 using a Pinnacle PCTV Pro, iuVCR, TMPGEnc and Nero. The resolution is 720x576 and the bitrate is 6000 bps. With this settings, I can fit a bit more than 1 and 1/2 hours in a DVD.

My question is: how come my Last Samurai "backup" to DVD5 preserves a good quality with almost 2 and 1/2 hours of movie, and my home captures show a quality drop with only 1 and 1/2, compared to the original captures?

BTW, I use CloneDVD to "backup" from DVD9 to DVD5.

Am I using the right tools? Can anyone with experience in VHS-->DVD give me some advices? Thanks a lot in advance,

Cirruz

[Floydscruffy]

Maybe I am wrong, but it usually is a source problem. maybe your source files dont have good quality, resolution, etc. When you encode them, basically you are faking them to 720x576 to become dvd compliant but maybe the source has less resolution and the encoding process wont fix that, aqlso the bitrate of 6000 u are using probably can be lowered to lets say 3500 and see no different, depending on how much motion the video has, and get more ours on the dvd for burning.

I recently authored a video with excellent quality in 5000 bps and then reauthored used 3000 bps and both looked exactly same while watching it on the tv. Definetly the 3000 bps one used only 3.5 Gigs and the other was 4.3 something Gigs. It could be that if I used my zooming option lon the DVD I would have noticed something!!!

hope this helps you a little.

[daamon]

Hi Cirruz,

VHS tapes, as a source, are at the resolution of 352 x 240 - that's why the picture isn't that great when compared to DVDs with a resolution of 720 x 480 / 576 (NTSC / PAL) - i.e. DVDs have at least 4x the amount of information on the same screen, hence a better definition picture per square inch / cm (take your pick - you get the point I hope).

Because VHS is only 352x240, when encoding with TMPGEnc try 1/2 D1 - 352 x 480 / 576. This reduces the amount of information (but not going below that that's already there), and so reducing the bitrate which, in turn, reduces the filesize and so (gasp for breath) means that you can get more on to a DVD5.

Because 352 x 480 / 576 is higher than 352 x 240 you shouldn't notice any quality loss against VHS.

Encode using 2-pass VBR (min = 1,000kbps, average = approx. 3,000kbps, max = around 5,000kbps) at 1/2 D1 and you can get around 4.5 hours of good looking picture (compared to VHS) on to one DVD5.

Use the DVDRHelp Bitrate Calculator to calculate the bitrate for the length of the footage that you have. The result is what you should use as your average bitrate.

Hope that helps. Good luck...

[Cirruz]

Dudes, you rock! Thank you very much for the help!

Cirruz

[lordsmurf]

Hi Cirruz,
VHS tapes, as a source, are at the resolution of 352 x 240 ........Because VHS is only 352x240......Because 352 x 480 / 576 is higher than 352 x 240 you shouldn't notice any quality loss against VHS.

Absolutely, undoubtedly, complete false.

http://www.digitalfaq.com/understandsource.htm

[Supreme2k]

I thought the end to the title of this thread would be

...why is tgpo a "celebrity"?

[indolikaa]

352x240 is NOT VHS resolution.

[jimmalenko]

Hi Cirruz,
VHS tapes, as a source, are at the resolution of 352 x 240 ........Because VHS is only 352x240......Because 352 x 480 / 576 is higher than 352 x 240 you shouldn't notice any quality loss against VHS.

Absolutely, undoubtedly, complete false.

http://www.digitalfaq.com/understandsource.htm

hmmmm, so resizing up doesn't make the picture look shit, eh ???

As I understand it, VHS is very close to 1/2 D1, this is why it is recommended so often as the best res to use if capping from VHS.

[daamon]

Hi Cirruz,
VHS tapes, as a source, are at the resolution of 352 x 240 ........Because VHS is only 352x240......Because 352 x 480 / 576 is higher than 352 x 240 you shouldn't notice any quality loss against VHS.

Absolutely, undoubtedly, complete false.

http://www.digitalfaq.com/understandsource.htm

I'm surprised lordsmurf, normally you follow up with why it's wrong. I know you supplied the link - and I did read it - but I'm still confused as to why it's "Absolutely, undoubtedly, complete false". Especially as I've used this as a source of info:

https://www.videohelp.com/glossary?V#VHS

EDIT: In retrospect, I think I should've quoted VHS as a resolution of 320 x 240 (not 352 x 240), but now I'm not sure if even that's right...

I don't mind being wrong, and I know I'm certainly know expert - as jimmalenko says: "As I understand it, VHS is very close to 1/2 D1, this is why it is recommended so often as the best res to use if capping from VHS" - I've seen this so many times, and I have to confess it makes sense to me, that I used it as the basis of my response to Cirruz.

So, for my benefit as well as for Cirruz, what is right? Where am I mistaken? I'd like to get this right for my own peace of mind and also so my future replies are correct. lordsmurf? indolikaa?

@ Cirruz - Apologies, as it seems I may have mislead you in this particular area.

[lordsmurf]

I'm surprised lordsmurf, normally you follow up with why it's wrong.

I've been busy lately, so I tend to stay brief. The page I linked to does have all the info there.

Anyway, VHS is about 300x486 in theory, or 225-250x486 in practice. Six are chopped off to x480 in DVD world. You're far shy (by half depth) and not accounting for interlace with a x240 resolution, and then overshot for clarity (about 40-100 too much using 320-350x size).

[Nelson37]

Ah, the old chestnut once again.

The resolution of your source is FAR LESS IMPORTANT for capture quality than what your card does at various resolutions. Most cards have a set capture res and resize and/or filter to achieve the specified capture resolution. Most of these resizing operations do unpleasant things to the video, with most cards showing a dramatic reduction in quality at right around 352x480, actually slightly higher.

Using a capture resolution of 640x480, or 704(720) x 480, will generally give the best result REGARDLESS OF SOURCE RESOLUTION. There are lots of mathematical permutations regarding the on-board resizing and/or filtering, as always, YMMV.

Remember that to cap an analog source with an apparent resolution of 352x240, or thereabouts, with a capture resolution of 720x480 does NOT involve a resizing operation, simply an overkill of applied resolution. BUT IT DOES AVOID ANY CAPTURE-CARD-BASED RESIZING OR FILTERING, and this is the important point far too many people ignore.

Actual field experience ALWAYS trumps theoretical considerations.

As for your two comparisons, the DVD rip is a near-perfect source, the capture file far from perfect. The percieved loss in quality on the cap source is mostly due to the smaller margin of error available. It's kinda like having a million dollars and losing ten, or having a hundred and losing ten. The loss is the same, but much more noticeable in the second case.

[daamon]

@ Lordsmurf - Ah, I think I get it now - that makes sense. Especially the "and not accounting for interlace with a x240".

Thanks for the prompt response and info - much appreciated.

@ Nelson37 - Interesting stuff. Certainly enlightening. So, in brief, capture at a high res so the capture card doesn't (may not) screw it up. I'd guess that the last step is to then encode at 1/2 D1 to get loads on to a DVD.

[Cirruz]

Encode using 2-pass VBR (min = 1,000kbps, average = approx. 3,000kbps, max = around 5,000kbps) at 1/2 D1 and you can get around 4.5 hours of good looking picture (compared to VHS) on to one DVD5.

daamon, thanks for your response. I've inserted those values into VideoHelp Bitrate Calculator, and it only gives me about 3 hous and 15 minutes of video... Am I missing something? I guess 4 and a half hour need something like 2000 kps, right?

Cirruz

[daamon]

Hi Cirruz,

The average I quoted was a rough figure. You need to go back to the bitrate calculator and feed in how much (in terms of time) you want to fit on to one disc. The bitrate it gives will be the average bitrate for you to use.

Remember, the lower the bitrate the more you'll notice imperfections in the picture. At what point it becomes unacceptable is down to you, but most people go for around 4 - 4.5 hours at 1/2 D1 on a DVD5.

Good luck.