Capture YUY2 is the only suggested way?

[Phoebos]

First of all Merry Xmas to all of you!

I m wondering why we should capture in YUY2 format and not in UYVY or RGB. Can you please tell me what is this all about? I mean YUY2 for capturing format is the only way for some reason?

I m trying to find out why the bright VHS areas are getting plain white (burned) in captured avi and think of any possible cause...

Thank you in advance

[junkmalle]

First of all Merry Xmas to all of you!

I m wondering why we should capture in YUY2 format and not in UYVY or RGB. Can you please tell me what is this all about? I mean YUY2 for capturing format is the only way for some reason?

I m trying to find out why the bright VHS areas are getting plain white (burned) in captured avi and think of any possible cause...

Thank you in advance

Like RGB, YUV is a system of representing colors. It uses an intensity value and two color components rather than Red, Green, and Blue. It is essentially the same format that television is broadcast in (black and white TVs only display the intensity signal, color TVs use all three). YUV is what's carried on the Y, Cb, Cr cables on higher end equipment.

But the color portion of a television signal is broadcast at half the resolution of the black and white picture. So fewer U and V values are needed to encode the color. Most video capture devices work in this native YUV colorspace. They capture color with less resolution than the intensity because that's the way it is broadcast. So instead of:

YUV YUV YUV YUV YUV YUV...

you get:

YU YV YU YV YU YV...

Or something similar. Note that every Y is surrounded by a U and a V (except at the very edges) so you can generate a full YUV value at each pixel (for converting to RGB or whatever).

YUY2 and UYVY are simply different orderings of this same information. I think most capture programs have simply standardized on the YUY2 ordering. And since the capture programs use that order the editing software does the same.

But all this probably has nothing to do with your problem! If the high intensity areas of your captures are getting washed out you probably are just capturing at too high an intensity. See if your capture hardware and software have settings that let you capture at lower intensity. Or try a VCR that's a little more sedate than the one you're using!

[BrainStorm69]

But all this probably has nothing to do with your problem! If the high intensity areas of your captures are getting washed out you probably are just capturing at too high an intensity. See if your capture hardware and software have settings that let you capture at lower intensity. Or try a VCR that's a little more sedate than the one you're using!

If you have a proc amp or proc amp controls in your capture software, try turning down the contrast a bit.

[Phoebos]

Thank you very much for your analysis.

Just discovered that the white like snow areas are not created in the avi but this is what the capture preview is so you are both so right. I mean that this is the way the VHS video is being captured by my Platinum Fly TV card (Phillips 3133 Chipset) . Watching the footage on TV it is ok.
I don t think that this is a capture card problem. Is it because the VHS tape is old?
Similar phenomena are observed in newer tapes but not so strongly.
Other colours and areas are more or less ok but white area is a disaster.

[junkmalle]

Did you try adjusting the brightness and contrast in your capture app?

[Phoebos]

Yes, I tried to reduce contrast from proc amp settings of MainConcept capturing features but this has only partially fixed the problem (too too much white becomes simply much) while other non white areas are becoming with poor contrast. So it seems there is no way to reduce only the unwanted washed white areas without at the same time give a bad result to the other non bright white areas. I am wondering why this thing happens...
Is there any filter improving only the white areas leaving the rest as they are?

Thanks again Junkmalle.

[junkmalle]

Yes, I tried to reduce contrast from proc amp settings of MainConcept capturing features but this has only partially fixed the problem (too too much white becomes simply much) while other non white areas are becoming with poor contrast.

Are you aware that computer monitors have a different gamma correction than television? Video should look dark on a computer monitor. But if you burn that to a DVD and play it on a television it will look fine.

Some information on monitor gamma:

http://www.bberger.net/rwb/gamma.html
http://en.wikipedia.org/wiki/Gamma_correction

[Phoebos]

Im afraid I have tried burned DVDs on tv and the result was no better....
Anyway thanks junkmalle.

[junkmalle]

There's one last possibility that I've heard of but never seen myself. Sometimes a device just puts out too much voltage. I believe a regular video signal runs from 0 to 0.7 volts. But it's possible your VCR is putting out something a bit higher, maybe 0 to 0.8, or 0.1 to 0.8. This could cause the video capture chip to overload in the bright areas. This is a case where an external proc amp can be used to fix the problem. Or you could borrow a friends VCR and see if that works better.

[Phoebos]

I used a voltage meter and the signal from video RCA output (composite) did not exceeded the values junkmalle mentions. I am trying to use "level" filter of VirtualDub but the correction is not great. Its a pity...I have VHS tapes with my son in the Olympic Games of last summer and almost everything under the sun gets white. Water polo games? Forget it, you cannnot distinguise the players the water and the ball...I don t know what to do.

[junkmalle]

A voltage meter can't accurately read megahertz signals. You need an oscilliscope to determine if the the video signal is outside spec (unless it was WAY out of spec).

The easiest thing to do is just try another VCR or another capture card. There is clearly something wrong with your setup. I assume that your VHS plays properly on your TV since you haven't mentioned anything wrong with that -- so it sounds like your capture card is messing up.

Could you post a sample image showing the burned areas? Maybe seeing the exact problem will help...

[SatStorm]

In your case, just go and buy a canopus 50 device... You can find it at "Grami" stores at Sturnara street (center of Athens)

- In Greek -

An 8eleis telia poiotita eikonas, pare tin canopus 50 (i 55). Kanei gyrw sta 200 eurw, alla einai oti to kalitero gia metafora analogikis pigis video se ypologisti. Tin karta 8a tin breis stin Grammi.

[Phoebos]

These are some frames which make the problem obvious. The capture was not with the default values of MainConcept Video Proc Amp option but
where changed as follows:

Brightness : 111 (def=128)
Contrast : 52 (def= 68)
Hue : 0 (def= 0)
Saturation : 64 (def= 64)
Sharpness : 0 (def= 0)

You realise that if I would leave the default settings the result would be much much worst...
Thank you Satstorm, but I m trying to do the job with my psesent capture card since the job is decent beyond this "wash out" problem. I know "Grammi" stores, from there I bought my NEC 3500 as well as my HDD WD. If i get completely dissapointed evntually I ll go for a Canopus

[Phoebos]

[Phoebos]

(the black guy was not me but a very funny guy from France!)

[Phoebos]

I think you have now an idea about my problem

[junkmalle]

I can see why you're unhappy! Have you tried turning down the saturation?

[Phoebos]

saturation down? but the colors will not be good after...

[junkmalle]

What makes me think the saturation is too high is the fact that parts of the picture which should be brightest white are around (R,G,B) 230,230,230 but the pool water has values like 110,255,255. The brightest white features are darker than the color features. That is what happens when you push the staturation too high.

The black level is bad too. The darkest parts of the pictures are overly bright. You should try lowering the brightness and the saturation.

I mentioned this before, but images on a computer monitor will be much more subdued than on a television. Dark areas will be much darker on the computer.

You should also make sure your monitor is adjusted properly. This is only a quick test but you should be able to differentiate every one of these grayscale bars except a maybe a few at the darkest and lightest shades:



Don't use this chart to adjust your video captures. The darkest and lightest shades are outside spec for video.

[canadateck]

From U to Z looks "Black" Is that bad?

[canadateck]

I'm on my other computer and it's all Black from W to Z.

[junkmalle]

On my monitor with the white IE background W is clearly visible, X is borderline. Y is just barely visible if I enlarge the image to get rid of the white IE background. Z and the bar to the right are both black. You're monitor doesn't sound too far off.

This message has some useful charts:

https://www.videohelp.com/forum/viewtopic.php?p=1148738#1148738

The message above it has some links to sites with more charts and such.

[SatStorm]

Cables.... Can you try other cables?
I have this kind of picture when I use composite and really low quality cables...

[Phoebos]

Hmmm never thought of cables...
and from W to Z its the same blalck for me also

[vhelp]

@ Phoebos

Are you using an amplifier or video distribution box in your
video ??

This is the same thing I had suffered from with my Analog boxes. I used
to use a 4 box amp from Ratio Shack a few years before I realized that
this off color became known. It may be your cables as well, or in combination
to your device (if you have one of these) in your setup.

(
.. By the way, this is known as color washout (IMO) because the colors
.. do not line up (whites of pail, and blacks are rusty looking, much
.. like in your pics.
)

-vhelp 2973

[Phoebos]

No vhelp I m not using any of those...
Now I want to find the time to go for new (not cheap this time) cables , mabe not from VCR Scart to Cap card's Composite but from VHS Scart to S-Video .

[vhelp]

I seem to recall that scarts usually cause this issue with this color washout
issue you are having.

.. After more than two weeks, you finally tell us that you're using a "scart"
.. connection

I think that way back in the earlier days of the ADVC-100 adventure and Will Hay
days, he had this or similar issue, and it was due to, or was "scart" related
in some way.

I think that the answer was solved there, but I forget the link

Maybe here, in one of these 12 pages:

* ADVC-100 vs ATI Radeon - Screenshots

or.., maybe here, in one of the 5 pages:
* Canopus ADVC-100 supporters - make your voice heard !!!


-vhelp 2979

[SatStorm]

Vhelp: SCART is the standand for us in Europe. All VCRs / DVRs / DVD-Rs / DVBs / TVs have it: There european VCRs for example, rarelly offer composite - out, only 2 SCARTs (and if you have a S VHS, you may be lucky and have a S-Video out!)
SCART are good connections overall: They offer you S-Video or RGB and always composite. The problem is that the cables they give when you buy something that use SCART, are the lowest possible way (and not 2 way, as SCART has to...)

@Phoebos
I grab through SCART myself and there is a difference between the cables. And a cable more than 1.5 metter is a problem you know...

[Phoebos]

Satstorm the cable is not very long but it is something I have bought at Praktiker (meaning cheapo) unterestimating the role of the cables ...Now I have to try something more decent and if Im lucky I won't be having wash out problem anymore.
Vhelp, the default connection here is via scart as Satstorm was saying. My VCR is giving the ability of connection via 2 Scarts and 1 RF...

[vhelp]

So, if anything, it could turn out to be any one of these:

* VCR
* Cables

etc.

-vhelp 2992