Feedback Take infrared and gray scale screen shots

I am having a project in which I am taking screen shots of the game using Render Texture. I wanted to take those screen shots n gray scale as well as Infrared. Any help will be good ..Thanks in advance.

 

"Infrared" is not a thing in Unity. Computer renders in RGB. So to have some sort of "infrared" render, you have to implement it as a material or a filter. Same goes for Grayscale render. You'd need to implement it as a shader, or use Post-processing Image Effect stack.

https://unity3d.com/how-to/image-effects-with-post-processing-stack

 

Or, for the greyscale, simply implement it in code yourself after taking the original screenshot.

https://en.wikipedia.org/wiki/Grayscale#Converting_color_to_grayscale

 

The first thing I'd try is Color Grading in the PP stack. Go heavy on the red for the infrared effect. Probably just kill all color saturation for the grey scale, but haven't actually tried that one. See if the effect is acceptable, since this is extremely easy to implement. Making your own shaders for everything to do it would be far more time consuming.

https://docs.unity3d.com/Packages/com.unity.postprocessing@3.0/manual/Color-Grading.html

For infrared you could also try just setting all lights in the scene, and any ambient light, to only emit red color instead of near white.

 

Or a LUT. Grayscale would be really easy with a LUT. Fake infra red would require some experimenting but might not be difficult depending on your image editing software. Somehow you need to convert the brightness into a hue.

 

You could try do something with night vision.
For example this one (mind, I have not tested it beyond Unity 5)
https://assetstore.unity.com/?q=Deferred Night Vision&orderBy=1

But also see other assets on the topic.
https://assetstore.unity.com/packages/vfx/shaders/fullscreen-camera-effects/deferred-night-vision-43423?q=night vision&orderBy=1

See "thermal" keyword.

 

That's not exactly how infrared works.

Spoiler

Examples of infrared photography:





https://petapixel.com/2018/05/24/why-infrared-images-look-the-way-they-do/

You'd really need a material system. If the idea is to make it look right, of course.

 

I've never seen that sort of infrared photography. I thought the OP was talking about this old-timey type of thermal imaging:

 

That is also what I assumed, but @neginfinity's point remains. Either way, IR rendering requires information which is not available in the RGB channels of our textures.

In the same way that you can't tell what the red component of a colour is if you only have the blue value, you can't tell the IR value from the RGB channels. You need a new channel in your data, which means new materials and potentially shaders.

For instance, in the above example image the person probably doesn't have blue hair and an orange forehead. There is no way to derive those colours from the textures provided under normal circumstances unless you outright make stuff up in your shader. Which might be fine, depending on the needs.

 

To be precise, OP really is asking for thermal vision effect.
Meaning world would need have some sort of informations, what is hot and what is cold. Shaders could be one thing. Or just having secondary textures, with heat signature.

 

That's thermal imagining. Not quite the same thing as infrared photography.
https://physics.stackexchange.com/q...fference-between-thermal-and-infrared-imaging
https://en.wikipedia.org/wiki/Infrared_photography

Consumer grade night vision IP or security cameras also frequently employ infrared vision. Such camera often comes with an infrared led projector which turns on during night time when the camera switches to night vision mode. Those cameras only record grayscale infrared, though.

Also, even in case of thermal imagining, you're going to need a heatmap or a way to track object's temperature. Which means you're going to need custom materials.

 

Usually game (and movie) implementations don't actually want a realistic implementation for this kind of tech though.

 

If we would implement it we would want it realistic

Edit: though this is not easy since we are missing info. For thermal imagine we need heat and conductivity. For IR we need lightsources to take infrared into account and it spills over to entire GI