(Capturing)-filtering-encoding: best way to go(vhs2dvd)?

[jeremypps]

Hi everybody.
I'm planning to buy a dvd burner in the immediate future so I'm beginning to read some documentation on how to create good dvds.
In this case question is about converting old vhs tapes to dvd.
As I've read in some posts, it would be a good idea to do some filtering before the final encoding process. Some talk about a temporal smoother.
I plan to use virtualdub for capturing and filtering and tmpgenc for encoding.
I live in a PAL country (Italy).
Let's say I capture at 720x576 with Picvideo mjpeg (I don't ask questions about this because I guess I'm in the wrong forum, but any hint is welcome ...).
Main question is: should I do the filtering while capturing? if not, when and how should I do it?
Does anybody know about a good guide on the subject?
Thanks in advance to everybody, hope I was clear, cheers, Jeremy.

[hypercube]

My goal is close to yours: I want to convert Old videotapes to SVCD.
Becareful, if your vhs are very old, you must use a very good capture
card. I mean, a card witch can capture very bad video signal with few
frame drop. My Asus V7700 Ti Deluxe, work very well. If you plan to
capture old VHS with a PCTV rave: forget about it !

the best way is to buy a capture card with Time Base Corrector inside
(TBC) but it is very expensive. Take a look of capture processor in
each capture card, you see if they are good or bad.

if your hardware is good, you will not in trouble.

[jeremypps]

thx hypercube for the answer.
I already have a sapphire radeon 9000 vivo and I cannot spend any more euro on the pc (my wife would kill me ...) apart for the burner.
I've seen the card works quite good on most tapes, but for 2 tapes a friend of mine asked me to capture (holiday recordings video8 reversed to vhs) I had to give up, too many frames dropped.
anyway, I gotta go on with this system, so I guess I'll have to do some filtering and I need help on how to.
thx to everybody.

[shito]

I would be really interested in this, too. I´ve been doing some capturing (PAL, NTSC, VHS, Laserdisc) and converting/authoring it using the Canopus ADVC-50 and Pinnacle Studio 8. Any suggestions on optimising the output would be welcome.

Greets
Konrad

[hypercube]

So we want to make VHS restoration. Let me tell you: This is a very hard task. Don't expect a perfect restoration if your videotapes are very
old.

1. Audio noise
The best way is to use CoolEdit Noise reduction filter. You take the
noise fingerprint and you can substract it to the entire movie soundtrack.
so you need to extract audio from your capture to a WAV file.

2. Video noise
In most cases:
- the video signal is less noisy on Luminance channel (Y).
- The chrominance channels (U & V) are very noisy.

So the trick is to keep the Y channel of each frame and make
some average on U and V channels.
- spacial average: blur effect not so good.
- temporal avergage: very good with old tapes BUT
- cut scene must be perfect
- motion detection must be good to avoid blur effect


if your video tape is very very trashed, the Y channel will be also
noisy. So you should make average also on Y channel.

Witch Filter to use ?

VirtualDub TV filter can make good result with the setting:
I/Q 5x5/temporal soften. But in fact it doesn't work on every
cases. So I don't use it.
This filter does not produce good result with
- scene cut: you can see the U/V fantom of the previous frame in the
first frame of the new scene. Very bad.
- motion with red objects: fantom effect.

You can also use the temporal smoother with filter strength = 2.
This filter make good result (perhaps not better than TV filter,
but it works on any cases !) with not so bad videotapes.

Most of noise reduction filters I seen, use a "magic threshold value".
This is why there are unsuable. In fact, there is an optimal threshold
value on each frame (or each scene) !
The only way to make a good video filter is to use statistical information.
So it is a good way to use multipass noise reduction filter.
This type of filter is rare.

Currently, I'am working on this type of filter, but it is very difficult.
The Motion detection is the main problem.

[shito]

That sounds interesting. Thanks for the reply, I´m gonna try some your suggestions tonight as soon as I get home. The DVDs I´ve been making were very close to the source (the tapes aren´t that wasted and the LDs are in best possible shape), but maybe I can even improve the picture quality compared to the originals, at least the perceived quality. We´ll see ...

Greets
Konrad

[jeremypps]

hi hypercube, thanks a lot for the reply.
I'm not so confident with filters but, most important, I don't know exaclty how to use them to then feed tmpgenc, i.e.: should I filter while capturing or should I do the filtering after that? if so, which are the steps?
anyway thanks a lot again, I'll copy and paste your answer in my "how to" notes, cheers, jeremy.

[shito]

Maybe I can shed some light on that: what you do is use your filters in VirtualDub, since you will only be using TMPGEnc to encode to MPG2. You can either frameserve with VirtualDub (find instructions elsewhere or just fiddle it out, its in the file-menu, somewhere) or, if you have enough HD-space, save a temporal .AVI with filters applied and feed this to TMPGEnc.

But this is all just shoveling bits and bytes to and fro, the true secret is in the filter chain, meaning what filters to use and how to set the parameters. This is where I´m hoping to get enlightened by the specialists in this forum.

Greets
Konrad

[hypercube]

this is not very usefull to filter during capture.
Use a good codec like PICVIdeo MJPEG with
freeVCR.

then you can use VirtualDub to filter and frameserve to tmpgenc

But this is all just shoveling bits and bytes to and fro, the true secret is in the filter chain, meaning what filters to use and how to set the parameters. This is where I´m hoping to get enlightened by the specialists in this forum.

there is no secret because there is no real solution. I most cases
you can apply only one filter setting for the entire movie. This is
not realistic. So the result will be "not so bad", but never "very good"
perhaps, if your movie is not very old, you will be able to perform
a good restoration.
And don't forget, a good filter setting for one movie can be not so good
for another movie. So nobody can tell you "do it like that and you will
have the best restoration of the world"

note that:
tmpgenc filters are spacial
virtualdub filters are spacio-temporal

is there anybody here who can tell us if there is a
multipass spacio-temporal filter around ?

[jeremypps]

hypercube, thanks again.
I can guess it's better to do the filtering in virtualdub rather than using tmpgenc's noise reduction or others.
trying to sum up, could we state something like the following?

VHS TO DVD - BASIC STEPS

1) Capture the vhs tape to your hdd at full resolution, choosing uncompressed, huffyuv or mjpeg avi;
2) open the captured file in virtualdub;
3) open the filters window and choose the desired filters, keeping in mind there is no best filter at all, but it depends from the source. Good choice to try is temporal smoother with filter strenght=2;
4) start virtualdub's frameserving;
5) run tmpgenc, open the frameserved file and load the dvd template. Play with bitrate until you find the best for you (maybe you can start loading the vbr template, choosing 2 pass, 8000 max, 2000 min, padding enabled, 4000 average, then play with the average value until the size prediction fits your needs);
6) burn the mpg

do you (or anyone else) think this basic steps are correct?
of course I can't do any try until I buy a burner, but I would wait for the sony multistandard; here in italy it's really difficult to find, while I've seen in the states you can buy on line for about $300, which would be a good deal ...
I guess I'll wait for another one or two months, meanwhile I'll begin to try the first 5 steps of the process (if you state they can be quite correct).
I have to thank you and all other people in the forum for sharing your knowledge and helping beginners like me to improve their skills.
cheers (and sorry for terrible use of english language), jeremy.

[hypercube]

if you state they can be quite correct

it was.

beware of multipass with temporal smoother because
there is a shift in frame apparition. See the virtualdub
warning when you will launch the frameserving.

[jeremypps]

hi hypercube, here I am again.
if you get bored about this just tell me.
yesterday I did a try and in fact I got that warning, so I removed the filter.
what should I do? I mean, should I ignore the message and go on with filter enabled or should I add something to the process?
anyway, I captured the same scene (1997 escape from n.y., when yena is in the ring fighting with that big ugly man), 20 seconds, first directly as mpeg2 with mmc, then mjpeg with virtualdub and mpeg2 with tmpgenc: well, birate was the same (vbr 8000 max) but the mpg made with tmpgenc was much cleaner, even with no filtering at all (vhs was in a pretty good shape, recorded from satellite).
I'll do several more trials in the next weeks, so when I get this damned burner I can say I'm quite experienced...
thanks again, cheers, jeremy.

[hypercube]

should I ignore the message and go on with filter enabled or should I add something to the process?

yes, ignore it.
it work perfeclty in single pass.
but I don't know in multipass.

the video noise in VHS is not a good friend of MPEG2
algorithm. in fact, I use the temporal smoother to
improve MPEG2 quality, more than restoring the
image quality.

[DJRumpy]

You should also consider trying a simple 2-d filter. Since your using VirtualDub, you can fin it here:

http://shelob.mordor.net/dgraft/2dcleaner.html

You should capture with a lossless codec like Huffman, but be warned that the file sizes can be extremely large (20+GB).

Use a bitrate calculator to find the highest possible average bitrate you can use, to fit onto on DVD-R. The bitrate calculator hosted on this site is an excellent one. Find it in the TOOLS section.

Since your source is VHS, you should also clip the edges of your video. They are often 'noisy' due to head noise, which eats up bitrate. Block out about 10 pixel widths from all four sides.

Last but not least, check to see if your VHS source is telecined. You can try inverse telecine to restore it to it's true 23.976 fps. This won't work on a true interlaced source, or pal sources. Learn about telecined material here:
www.lukesvideo.com

[jeremypps]

@hypercube
hi and thanks again. I have to do some tries and see what happens, hope to find some time in the immediate future to do it.

@djrumpy
hello, thanks for the kind reply.
I've downloaded the vdub filter, think I'll try this as well in the next days and see what happens.
I'm in a pal country so I won't ivtc.
a couple of questions:
- do you think using picvideo mjpeg (quality 18/19) instead of huffy can provide a big quality difference for tmpgenc feeding?
- about the cropping: when and how should I do it? I mean, during capturing, while frameserving or in tmpgenc while encoding?
sorry if I ask dumb questions but I'm quite a newbie and I need step-by-step hints; moreover, as you can see, I'm not so confident with english language ....

thanks again to everybody, cheers, jeremy.

[DJRumpy]

- do you think using picvideo mjpeg (quality 18/19) instead of huffy can provide a big quality difference for tmpgenc feeding?

This is entirely up to you. Quality is a very subjective thing. If your happy with the MJPEG output, then use it. Huffman will give you optimal quality since it's lossless. MJPEG is lossy, meanning some detail is lost during compression. This sort of thing is something you have to decide for yourself. Preferences aside, if you have the disk space available, use Huffy. If not, stick with MJPEG.

- about the cropping: when and how should I do it? I mean, during capturing, while frameserving or in tmpgenc while encoding?

You can actually do this in any step, except during the actual encoding. If your familiar with AVISynth, or VirtualDub, I'd suggest you do it there, but you can do it with TMPGenc as well. If your capturing with VirtualDub, you can even crop it during the capture. I usually do it during the filtering/frameserving session. That way, if I get it wrong, or clip too much, I always have my 'pure' source to start again. Again, it's up to you as to when. It doesn't really matter when.

Don't worry about the questions. The forum on here is one of the best I've run across. Everyone's usually more than happy to help out. Your English is fine by the way...

[jeremypps]

hi Djrumpy.
unfortunately I've never used avisynth, I think I'll stick with virtualdub as it's more user friendly to me, even if, reading various posts, it seems that avisynth is more "powerful".
cropping while filtering is best choice for me as well, I'll try and try and try and see what happens.
many thanks again, jeremy.

[DJRumpy]

To crop in VirtualDub, open the Video Filters menu, click the ADD button, and find the Null Transform filter and select it. Once you do that, the "Cropping" button should become available on the mail Video Filter screen. The interface is pretty simple. Just post if you have any problems.

[Don2050]

This thread may help a little...

https://www.videohelp.com/forum/viewtopic.php?p=258622&highlight=flaxen

https://www.videohelp.com/forum/viewtopic.php?t=148876&highlight=hwoodwar