Netflix Makes Removing Green Screens Easier by Turning Actors Bright Purple | Hacker News Reader

Netflix Makes Removing Green Screens Easier by Turning Actors Bright Purple

gizmodo.com

13 pointssohkamyung6 comments

I was thinking they were somehow controlling the light so the colour saturation never “peaked” on good cinema grade cameras. That way, it could be colour graded back to normal by turning down the magenta saturation. (I’m no expert, so this is the wrong terminology I bet, but I’ve messed with the “tint” slider in Apple’s Preview.app that does give everything a magenta/purple hue if you crank it up.)

However, this says they’re using an ML colourizer tool to un-magenta the image after it’s been masked? Why not just invest in ML tools that can make a greenscreen mask for you? I actually think that already exists at a pretty advanced level. (Considering it’s already very common on phone cameras and video chat apps, with surprisingly good results)

This seems like a lot of effort to just make the mask layer an “in camera” effect. Maybe there’s a good reason for that?

It almost never happens in real life so normal photographers don’t have to deal with it, but if there is no green color at all (e.g., you mix magenta and blue so your green pixels are all at noise floor) then you cannot bring it back from nothing as you color-balance raw footage. You would have to do some coloring.

However, human perception is such that color is much more subjective than things like artefacts from green screen separation, so it might actually not be a big deal.

Being able to preview effects while shooting may be seen as a potential way to save production costs by removing some of the need for re-shoots and pickups.

Linus Tech Tips covered their new Blackmagic Ultimate green screen appliance which was a fun trip. $2500. https://youtu.be/_CxkmtBqGn8#t=30

I thought this Purple mention was there too but I'm not seeing it; I know I'd seen in mentioned sometime around then. Already really good performamce from this box even without color hackery. I can definitely see how that purple pale could help aid filtering things down!

Couldn’t LIDAR help significantly here?

It’s funny - the test rig in the article shows wraparound LED displays, which are already replacing a lot of green screen applications: the scene is rendered in real-time on those displays, taking the position and angle of the camera as input to get the perspective correct: there’s no masking to do, because the scene just “looks correct” in camera.

The Mandalorian was a high-profile early use of the tech. It’s pretty impressive!

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