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Automated color grading and color matching with a Machine Learning Algorithm — Page 4

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towne32 said:

Does incorporating an ‘outlier’ shot correction (one that the grader had to use different settings) have any negative impact on the algorithm for the rest of the film?

As long as all shots on that location are graded consistently, this should not affect the rest of the film.

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Darth Lucas said:

I gotta say I’m a fan of the VertaBot

Ditto. And since the real Mike’s gone radio silent, I say we hook VertaBot up to a chatbot and then we can have an active Legacy thread again.

Project Threepio (Star Wars OOT subtitles)

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DrDre said:

Stotchy said:

It’s so pleasing that there is potentially a solution to to appease everyone’s different color timing tastes without HUGE efforts of doing so manually shot-by-shot.

I for one am not a fan of the green technicolor look so Neverarbot and Vertabot alternatives are fantastic to have available!

RE your limited Verta references, can you use screen shots from Mike’s videos? Or will the Vimeo compression likely have messed with the colors?

If I understand correctly, the Verta videos are not graded yet. He first corrected Legacy to neutral colors, which he shows in his videos, and then does the color grading at the end. The four earlier shots all represent preliminary grades.

I’m just going off memory, but I assumed at least some of those videos were already graded, since he sometimes compared the color to the blu-rays and seemed to imply his restoration was how the movie was supposed to look?
Also, in the Yavin launch video when he compares the restored shot to the original print, he specifically remarks how much the “color grading” impacts the final shot in terms of dynamic range.

Again, just the impression I got from watching them, so I could be wrong.

*edit - I just watched another of his color comparison videos and he mentions that his version is how the technicolor print looked. So I guess I misunderstood and the versions in the videos are just simply corrected to match the techs and from there he does the final color grading. Is that correct?
Thanks.

“In the future it will become even easier for old negatives to become lost and be “replaced” by new altered negatives. This would be a great loss to our society. Our cultural history must not be allowed to be rewritten.” - George Lucas

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Dre, awesome job!

Idea: it’s possible to regrade a whole film using just a trailer for reference, right?

Sadly my projects are lost due to an HDD crash… 😦 | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com

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VertaBot is my favorite so far. What a great result!

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^…^ said:

Dre, awesome job!

Idea: it’s possible to regrade a whole film using just a trailer for reference, right?

I’d like to know the answer to this one as well.

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the shot of obi wan and luke in the desert in between NeverarBot and techbot would be perfect. also i thought the death star was gray not blue

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^…^ said:

Dre, awesome job!

Idea: it’s possible to regrade a whole film using just a trailer for reference, right?

In theory yes, but the quality of the final result will depend on the consistency of the source, and the reference. If the color grading of the source you want to regrade varries wildly, in the worst case it’s possible you might need a reference for each shot. Garbage in is garbage out.

The algorithm recognizes the colors of a scene, and ensures the colors for each scene for which you have a reference accurately matches the reference. For the scenes for which it does not have a reference it estimates the colors based on the sources it has available. This is why this method works much better than color matching a shot, and using a LUT based on that shot to correct other scenes. Such a LUT would only contain information about the colors in that shot. If for example another person would walk into the frame, the colors could be off by quite a bit, especially if the colors are altered heavily. The self-learning algorithm would use the color information of that person from other shots, without adjusting the colors of the rest of the shot, as each pixel is graded individually. This also ensures color consistency between shots.

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The Death Star walls in the original color timing were blue to varrying degrees.

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DrDre said:

The Death Star walls in the original color timing were blue to varrying degrees.

What about it on the outside is it blue or gray?

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Gray is a difficult color on film. Not only can gray have its own tint, but it can take on tints from lights and in the color timing process. In color correcting I’ve found the grays are the hardest thing to get right.

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Yeah, you’re right. There are also shots where it’s stained with green.

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You see the reason I have an issue with desert shot and some other shots is it seems too warm like they have completely yellow skin. Also some shots of obi wan he looks a little red still. Also on the death star there’s some color issues there as well.

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All evidence points to tatooine supposed to be very warm and yellow from the color grading but I would agree it looks better with a more natural grade.

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jedimasterobiwan said:

You see the reason I have an issue with desert shot and some other shots is it seems too warm like they have completely yellow skin. Also some shots of obi wan he looks a little red still. Also on the death star there’s some color issues there as well.

Like Darth Lucas said, the desert shots are supposed to be warm, and I personally don’t see yellow skin tones. The Death Star color grading is Mike Verta’s so take it up with him 😉. That said, these are based on just 4 reference shots. In practise you don’t regrade an entire film on four reference shots, which in this case did not even contain any desert shots.

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DrDre said:

jedimasterobiwan said:

You see the reason I have an issue with desert shot and some other shots is it seems too warm like they have completely yellow skin. Also some shots of obi wan he looks a little red still. Also on the death star there’s some color issues there as well.

Like Darth Lucas said, the desert shots are supposed to be warm, and I personally don’t see yellow skin tones. The Death Star color grading is Mike Verta’s so take it up with him 😉. That said, these are based on just 4 reference shots. In practise you don’t regrade an entire film on four reference shots, which in this case did not even contain any desert shots.

what about the scene in the lars home owen looks yellow and beru and luke look wrong as well.

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jedimasterobiwan said:

DrDre said:

jedimasterobiwan said:

You see the reason I have an issue with desert shot and some other shots is it seems too warm like they have completely yellow skin. Also some shots of obi wan he looks a little red still. Also on the death star there’s some color issues there as well.

Like Darth Lucas said, the desert shots are supposed to be warm, and I personally don’t see yellow skin tones. The Death Star color grading is Mike Verta’s so take it up with him 😉. That said, these are based on just 4 reference shots. In practise you don’t regrade an entire film on four reference shots, which in this case did not even contain any desert shots.

what about the scene in the lars home owen looks yellow and beru and luke look wrong as well.

What scene in the Lars home? There is no shot of Owen and Beru in this thread, apart from the shot of Luke and Owen on the first page, which is a regrade by NeverarGreat.

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I’m working on an extensive test of the algorithm based on NeverarGreat’s preview of reel 4. I will be comparing the results of the NeverarBot directly to NeverarGreat’s regrades.

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jedimasterobiwan said:

DrDre said:

jedimasterobiwan said:

You see the reason I have an issue with desert shot and some other shots is it seems too warm like they have completely yellow skin. Also some shots of obi wan he looks a little red still. Also on the death star there’s some color issues there as well.

Like Darth Lucas said, the desert shots are supposed to be warm, and I personally don’t see yellow skin tones. The Death Star color grading is Mike Verta’s so take it up with him 😉. That said, these are based on just 4 reference shots. In practise you don’t regrade an entire film on four reference shots, which in this case did not even contain any desert shots.

what about the scene in the lars home owen looks yellow and beru and luke look wrong as well.

Or when Yoda hands Luke the pipe?

“People who alter or destroy works of art and our cultural heritage for profit or as an exercise of power are barbarians”

“In the future it will become even easier for old negatives to become lost and be “replaced” by new altered negatives. This would be a great loss to our society. Our cultural history must not be allowed to be rewritten.” --George Lucas on March 3, 1988

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So forgive my technical ignorance, DrDre, but how exactly does this work? Do you have to manually attach a shot to a source frame? Or does it take the bulk of reference frames you have and build a universally applicable model to grade any shot with?
And how is the grading accomplished? Does it just take the color palette of your references and match the source to it as closely as possible?

A detailed explanation of what steps the software takes would go a long way for helping a non-technically minded person like myself to comprehend what’s going on here.

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I would actually really like to see examples of this used on ESB Grindhouse - perhaps with enough regraded shots the color could be lured out.

Preferred Saga:
1/2: Hal9000
3: L8wrtr
4/5: Adywan
6-9: Hal9000

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nightstalkerpoet said:

I would actually really like to see examples of this used on ESB Grindhouse - perhaps with enough regraded shots the color could be lured out.

Ouch, LOL.