set a virtual object as the foreground

Studio Operators Camera Tracking Augmented Reality

 

Hi.

In the tracking camera with green screen environment, set a virtual object as the foreground of the camera's object, not the real object. I don't understand if there is a similar operation, maybe a mask, I don't quite understand what the current flow is. Please answer, thank you.

   Rain_law

 
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Renbry
8/12/2022 12:48:07 AM
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In Broadcast DE we use Virtuals/Billboard to have the image plane set into the scene. Therefore anything spatially closer to the camera than the image plane will composite automatically. In this context we don't need masks etc as the scene is set up logically. This may not apply to your setup depending on what you need.

I know there's a concept called "AR" in Aximmetry language - that seems to let you render a layer above the live action that you could look into.

Matt Hermans

Electric Lens Co.

 
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Rain_law
8/12/2022 7:19:41 AM
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Hi Renbry

I see that the document is indeed the effect we want, but there are also some problems. Compared with the tracking camera in green screen keying, it lacks a lot of modules. It seems that it cannot achieve two functions in one place, right?https://aximmetry.com/learn/tutorials/for-aximmetry-de-users/using-tracked-cameras-and-augmented-reality-with-an-unreal-scene/?_ga=2.71372563.1029504702.1659954735-282941165.1631955436

 
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Eifert@Aximmetry
8/17/2022 4:45:34 PM
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Hi,

You can use the AR Overlay input pin for this in tracked cameras if you use Unreal scene, it is detailed here:
https://aximmetry.com/learn/tutorials/for-aximmetry-de-users/aximmetry-and-unreal-combined-rendering/
Note, since only one Unreal with one camera can render on one computer. You either need to do the AR with Aximmetry's render engine or you need to use a multi-machine setup.

If you don't use Unreal at all, then there is no need for a multi-machine setup. Just use the Overlays input pin of the Tracked or Virtual camera compounds.

Of course, the AR part will need its own AR compound, for example, the TrackedCam_AR_Prev_3-Cam if you render the AR part with Aximmetry.

Note, you may need a much simpler setup, like if you just want to display the "AR" elements at one position of the screen and not in the virtual 3D world. If you can detail what you want to achieve exactly we might be able to suggest a simpler setup.

Warmest regards,

 
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Rain_law
8/17/2022 5:10:48 PM
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hi Eifert@Aximmetry

I haven't really understood what billboard is, because when I clicked on this function, I found that the real-time shooting material of my tracking camera disappeared, but I didn't see anyone explaining this point, maybe I didn't read the documentation carefully. And what does this virtual function represent? Could you explain it, please, thank you.

And what I want to achieve I will reply you later. thanks

 
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TwentyStudios
8/17/2022 6:48:06 PM
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@Rain_Law: If I understand correctly you just want to have objects in your UE4 3D scene appear in front of the person on the keyed green screen footage? In that case you just need to use Billboards and Allow Virtuals. If you4 footage disappears you probably haven’t setup your scene properly. Have you set the Stencil Pass and Global Clip plane in UE4  as explained in the documentation?

 
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Rain_law
8/18/2022 4:34:50 AM
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hi TwentyStudios

I just checked my UE settings, and the GLOBAL CLIP PLANE setting is not turned on. I didn't see the need for this setting in the document, maybe I missed it. But later I checked and I wasn't sure if this turned on was helpful, but the real video in aximmetry didn't disappear, which is a good thing. But it feels like it cuts half of the picture and I don't understand why. Another good news is that shadows can be simulated. Below is a screenshot of my operation.



 
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TwentyStudios
8/18/2022 5:46:04 AM
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@Rain_law: It’s important to follow the instructions closely for everything to work correctly. You also need to enable Custom depth stencil pass as described in the documentation:

https://aximmetry.com/learn/tutorials/for-aximmetry-de-users/getting-started-with-the-unreal-engine-based-de-edition/

You should also read the documentation on the keyer. Looking at your screenshots it looks like the settings are way off. You should move the High and low cut as little as possible from the 0 and 1 value respectively. 

 
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Rain_law
8/18/2022 1:47:20 PM
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hi TwentyStudios

OK, I'll turn this feature on. Regarding the keyer, I'm currently there to test the process. In addition, why is the lower part of it cut off as I said, is this normal? 

Thanks

 
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TwentyStudios
8/18/2022 5:58:48 PM
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Just read the documentation on working with tracked cameras. All will become clear. This forum is better used for questions where the answer isn’t easily available to everyone.