Ignore embedded alpha channel?

How do we ignore an alpha channel embedded into the EXR while displaying in presentation mode?

Check out RVDisplayColor, you could modify the color.channelOrder property to stick a 1 in where the A would be.


how exactly would I apply this?

It only seems to happen in presentation mode, is there a way I can force that onto the external display?

Humm, not exactly sure what that means, are you seeing through your presentation window? I’d have to defer to Autodesk support for that…

yes it’s showing the desktop background.

I’m wondering if this has something to do with the signal coming from a Quadro RTX instead of a AJA/Blackmagic card.

I think what you are seeing is “new” in the latest RV since 7.9. I would call it a bug, because it is definitely not wanted behavior and was not the case in earlier versions. In earlier versions in presentation mode, the entire background would be black, regardless of how much of the image filled the screen. Now, on an HD monitor, if you present a 2.39 aspect image for instance, we can see in the letterbox area whatever is already on the screen under the presentation image. Is what I am describing the issue you are having?


Yeah that also happens!

But additionally some of our exr renders have embedded alpha’s (not premultiplied) (for the client DI) and RV seems to premult them with some opacity setting.

So for instance, say we added a CG pillar and we put the matte for it into the alpha channel of the exr RV will display the presentation mode version of this with a 100% opacity pillar, and the rest of the image is somehow between 10 and 100% of opacity so our company desktop background shines through.

And indeed also because the image doesn’t fill the aspect of the TV the desktop background is seen top/bottom of the screen.

As another datapoint, on an RTX 2080ti under Windows 10, I am also seeing this behavior. The simplest way to reproduce this is to run this command (replace rv.exe with the full path to your rv if not in your PATH) (This also assumes you have a presentation monitor set in your prefs)

rv.exe blank.movieproc solid.movieproc -present -play

@jrab, @Ricardo_Musch, what OS are you on? IIRC, some of the desktop presentation mode code might be OS-specific.

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Windows 10 v2009

Quadro RTX 4000 in this case.
I will check if this happens too on our Blackmagic output.

Yes - I have an old ticket on this, and I see the ticket mentions it as a Linux issue. I haven’t been able to review to see if I have the same issue as Ricardo with alphas and exrs.

The blank.movieproc should replicate what’s happening with sources with non-1.0 alphas.

@Ricardo_Musch, given that the Blackmagic doesn’t display to your desktop, I would expect it just to mult against black.

@Autodesk, are you still taking bug reports through the forums here or do we need to file a separate ticket? Sounds like we’ve got some diverse hardware/OSes reproducing this.

Note, I’m getting this reproduced on 7.6.1, so I don’t think this is new to 7.9.0

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Unfortunately I’m in remote and the presentation display doesn’t work the same as being ‘live’, so I can’t really test for another few weeks. But this should be easy enough to test @Autodesk? I just updated my old ticket (#115531) with this thread.

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I found out what my problem was, maybe it’s related to the others:
When Centos desktop effects are ON, then we have the issue of the transparent background outside the image area in presentation mode.
When desktop effects are OFF, then presentation mode works like it did in pre 7.x n(7.8?) versions.- it masks everything