Using OBS projector windows with SMART ink

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obsjake

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I'm a school teacher and use OBS to mirror part of my screen to a projector connected to a SMART board.

SMART have some software called SMART Ink which allows me to write over the top of app windows using my finger/pen on the digital whiteboard. This works in 'most applications', such as Office apps, web browsers and even Notepad. However, it doesn't work over in the main OBS window or (most importantly) my OBS 'projector' window. As a result, when I'm using OBS in my lessons - as I do every lesson - I can't use the interactive whiteboard at all.

I've sent a support email to SMART asking them if there's a setting/option/flag that an app (such as OBS) has to set in order to, I guess, make it appear as an 'editable document' or something. My guess is it's probably as easy to fix as that. The fact this inking works in Notepad (which is just plain text) suggests all an app has to do is declare itself as an editable document or something for it to work.

Anyone got any ideas how/if this might be possible?

Jake
 
OBS Studio is software for live video content creation, either streaming or recording. Since you appear to not teach video production or directing classes etc, why do you want SMART to work on top of OBS?
What you try to accomplish is annotating an OBS output, while you most likely should want to annotate the input for OBS. When you ie. show a PowerPoint presentation and want to write or draw upon that, try to capture the PowerPoint window and the SMART overlay and feed that into OBS.
 
Thanks for replying WBE.

I'm a school maths teacher. On my main computer screen I have PowerPoint or other windows open, and I use OBS to output a part of that screen (or usually a cropped part of a particular app) live to the secondary display (which is a projector/smart-whiteboard). Usually I'm using PowerPoint in edit mode rather than presentation mode, with e.g. thumbnails down the left and all the toolbars, but I have OBS set up to crop the thumbnails and toolbars off the OBS projector output, so my students only see the 'slide/page' part of the PowerPoint. I do this rather than using PowerPoint in presentation mode, because I will edit the PowerPoint as I go through the lesson, and there's no reason for the kids to see the toolbars etc, I want everything to be as big as possible for them on the whiteboard projector.

When SMART 'inks' on top of an app, the data for that inking is stored separately from the app/document you're working on, and is interacted with via the SMART Ink toolbar. It's temporary, and disappears when you close the app, and you erase it, change pen colour etc within the SMART Ink toolbar. This is confirmed by the fact you can 'ink' over a basic plain text Notepad document. If I move that Notepad document around on the screen, the ink follows it, with a bit of a lag, and disappears on closing Notepad. Reopening the same Notepad document, and that temporary SMART ink is gone.

Currently I use a graphics tablet to ink within PowerPoint itself during class, but this is unideal. Better would be for me to be standing at the whiteboard, gesticulating with my arms and using my fingers/hands to show the kids things on the screen, while using my fingers/pen on the projector whiteboard via SMART Ink. Alas, because it doesn't work on top of the OBS projector this doesn't work.

So yes, I actually do want to annotate the OBS output (or at least, let SMART know the window is annotable-or-something so it lets me by giving me the toolbar, like it does for other apps like PowerPoint or Notepad). The only workaround I can think for this at the moment would be to layer a separate transparent app window on top of the OBS projector output, so that the SMART Ink toolbar appears for that.
 
I understand that you seem to want to annotate OBS's output, but you concluded that it don't work. My point is that, to draw a parallel, you blame a fork manufacturer that the products lack cutting possibilities. Just don't cut your veggies with a fork, instead use a knife.

Is this SMART Ink a Microsoft Windows application that runs at your computer? Then I think you should be wanting to capture both the PowerPoint window and the, apparently transparent, SMART Ink window on top of it.

As Tomasz mentioned, the most convenient way can be to use a Display Capture source. That will, as the name suggests, capture anything going on at that display, so if you'd ie. stack six programs partially over eachother, that complete stack of windows will be captured (at least the visible parts of windows).
Or you'd have two Window Capture sources in your OBS scene: one to capture PowerPoint and one to capture SMART Ink.
 
Thanks Tomasz. It's not about what I'm capturing, but the type of window the OBS 'projector' window is.

This is how my lessons look. I want to write on 'Screen 2' (the digital whiteboard) but can't, because the top-most window on there is the OBS projector output, which I'm guessing has some setting/flag which means SMART doesn't think it's editable or something (as before, if e.g. Notepad was top-most window, it allows me to ink on that, even though Notepad is just plain text). Currently if I want to use my pen, I have to do it via a graphics tablet instead, which is mapped to Screen 1.

WBE: Thanks again. Yes, it's a Windows application. No, capturing the screen doesn't solve the issue (I do switch to that 'scene' when I want to transmit my whole screen instead of just a part of PowerPoint, but usually I certainly don't as there may be confidential information about kids eg in emails on my main screen).

Imagine being in the classroom. Sometimes you're sitting at Screen 1 editing the PowerPoint file and students can see live as you do it on Screen 2. Sometimes I'll sit and use the graphics tablet, and again they'll see it live on Screen 2. But when I stand up I also want to be able to add this temporary SMART Ink directly on screen 2, because Screen 2 is an interactive whiteboard, with touch sensitivity. But because Screen 2 is just showing the OBS projector output, the SMART Ink doesn't work on it. Put a simple Notepad document on that screen, and I can SMART Ink fine on that Notepad. So there's some sort of setting in OBS' projector window which probably registers the window as not being editable or something, because SMART Ink seems to work over on all kinds of editable app windows.
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obsjake said:
So yes, I actually do want to annotate the OBS output (or at least, let SMART know the window is annotable-or-something so it lets me by giving me the toolbar, like it does for other apps like PowerPoint or Notepad). The only workaround I can think for this at the moment would be to layer a separate transparent app window on top of the OBS projector output, so that the SMART Ink toolbar appears for that
Click to expand...
You almost found out why your intended workflow from your opening post will not work.
As far as I understand, you are giving lessons and are streaming your sessions to your audience with OBS.
You are using the projector feature of OBS to cast the streaming output to an interactive whiteboard where you annotate this output.
Finally, you want your annotations also appear on the stream, so your audience will see it.

This will not work, because what you're seeing on the whiteboard and what you're annotating is already the final output. There is no capture of your annotations from the whiteboard back into OBS.

You need a means to capture this annotation overlay and add it as source to OBS, so it's included in the stream. I don't know that software, so I don't know if this is possible. May be it's possible to capture it like any ordinary software with window capture.

The direct way to capture the annotations is to not use the projector feature of OBS on the whiteboard, but instead directly use your whiteboard as monitor and move your apps (Powerpoint, Notepad, etc.) there and capture the whiteboard with display capture in OBS.
However, this way you cannot see the composited video (you said you cropped buttons and stuff away from the apps you capture) but see the original app.

If it is possible to capture the overlay by OBS (imagine just the ink you see, and everything else is transparent), there might be a feasible solution:
Create 2 scenes in OBS. The first scene is what you currently have. Use the projector scene to cast it to your interactive whiteboard. Make sure you right-click your scene and use "Fullscreen projector (Scene)" to cast it. Don't use the projector from the preview window!
To the second scene, add your first scene (look for the source type of "Scene"). Now you have a duplicate of your first scene. Additionally, add the capture of your overlay to that scene, so you see in the preview the annotations. Stay on this scene and do stream this scene to your audience. However, this will only work if you're able to capture the annotations overlay separately.
 
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Thanks Koala... but not quite. The audience (a class of school kids) is all in the room - I'm not streaming anywhere outside the room, only to the OBS projector window, which is the one that the kids see on the interactive whiteboard. I do not want/expect the annotations to appear 'in' the stream, but simply for the SMART Ink toolbar to appear on top of (i.e. over) the OBS projector window.

The SMART Ink toolbar seems to attach/overlay itself on top of regular app windows, providing a transparent canvas for drawing above them via the interactive whiteboard. But they say it works with "most applications"... but not all, and not OBS. My guess is that apps have some kind of flag in them which registers them in Windows as either editable documents or not. SMART then allows its toolbar to appear above editable documents (e.g. Notepad), but not others. I have of course emailed SMART separately to try to get their answer to this one.

And yes, I've thought about your solution re 2 scenes if I ever wanted to simultaneously live-stream my lesson to COVID-isolating students at home. But until the SMART annotation toolbar appears above the OBS fullscreen project window it's a non-starter.

This page provides the best clue I've found for why the SMART Ink toolbar doesn't appear above OBS:

Turning SMART Ink on or off - SMART Ink 4

support.smarttech.com support.smarttech.com

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The first bullet point isn't the case (I didn't turn it off for OBS), and neither is the second (OBS doesn't provide its own writing and drawing tools). Thus I'm guessing OBS has a flag that makes it appear to SMART as a "window that contains information you typically don't write or draw over, such as application settings".
 
I think that, on Windows you have diffrent type of drawing, e.g. GDI, DirectX (3D, DirectDraw), OpenGL.
SMART Ink use some Overlay to display on screen, probably some type surface can't be draw on other, I'm not talking about two windows, but about accessing the window handle and drawing in it by context.
 
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