How to darken a very bright video? An easy task?

[jairovital]

there should be no difference between panes if you just open the video in vdub (no filters)

disable direct x : options => preferences => display => uncheckmark use direct x for display panes

Yes, my Direct X was checked. When I unchecked it, the difference disapeared. But it was nice. I could see more details on left pane. Now, the details had gone and the image on pane is washed as the right one.

Actually it's exactly the same, if you are working in RGB . If you know how to use RGB levels in photoshop it's the same in vdub, in avisynth, in ae, etc... input white, input dark, gamma, output white, output dark

Yes, I'll try some tricks.

To create the 1st sample, I increased brightness and gamma in RGB, then I conveted back to YUV with full range matrix

How to conveted back to YUV with full range matrix?

[jagabo]

How to conveted back to YUV with full range matrix?

You don't need to convert back to YUV with the full range matrix. Your final video should have RGB blacks at 0 and brights at 255. The usual rec.601 matrix will convert those to legal Y values, blacks at Y=16 to brights at Y=235.

You only use the full range matrix for special purposes -- like preparing samples with superbrights to help people understand how to deal with them! You can do that in AviSynth() with ConvertToYV12(matrix="PC.601"), or ConvertToYUY2(matrix="PC.601"). You can't do it in VirtualDub. Some codecs have the option to use PC.601 matrix. So you can enable that option in the codec and feed it RGB with VirtualDub.

[jagabo]

Yes, my Direct X was checked. When I unchecked it, the difference disapeared. But it was nice. I could see more details on left pane. Now, the details had gone and the image on pane is washed as the right one.

If you leave DirectX enabled what you see in the left pane will depend on your graphics card's video proc amp settings. You should adjust those settings to standard video levels -- ie IRE 0 (Y=16) = black, IRE 100 (Y=235) = white. If you do that the two panes should match.

[jairovital]

Thank you, jabago, for your lessons. I was reading some threads where you post and I do know there are too many concepts I need to learn. Your contribution, as ones from poisondeathray are valuable at this forum. We, common users, are grateful for them.

[jairovital]

I mean stay in YUV space, using filters that work in YUV, like smoothlevels or smoothcurve or levels . If the superbrights values are preserved in the video then you can access them.

May you please, suggest some smoothlevels parameters? I'm reading doom9 LaTo explanations about SmoothAdjust, but getting poor results.

Below I'm using just gamma.


My input:

Loadplugin("DGDecode.dll")
Mpeg2Source("Untitled.d2v")
#ConvertToRGB(matrix="PC.601")
#info()
smoothlevels(gamma=.7, show=true)
#histogram()

P.S.: Since the first post I'm reducing the real size of the pictures to save space and bandwidth of the forum, but if it's necessary I'll post them in full size.

[poisondeathray]

May you please, suggest some smoothlevels parameters? I'm reading doom9 LaTo explanations about SmoothAdjust, but getting poor results.

Nope, it's clipped . Poor results are normal and expected

Since it's clipped, even working in YUV makes no difference (everything is between Y' 16-235 already, there is no data > Y' 235 left to save)

[jairovital]

Ok. Moving on. I insisted because I could see data beyond 235 at the samples you sent previously. And I tought it would be possible to grab it.

[poisondeathray]

Ok. Moving on. I insisted because I could see data beyond 235 at the samples you sent previously. And I tought it would be possible to grab it.

But the video you are using is badly clipped (there is nothing in the brown region to recover). , and what is left over is all "squished" in that Y=235 line. It's too far gone as jagabo says

The other samples I uploaded have clipped version and a non clipped version. Try improving those - the non clipped version it's possible to recover some data and improve it.