logo Sign In

Color matching and prediction: color correction tool v1.3 released! — Page 34

Author
Time

Dre, if you are planning to make some improvements… a way to batch jobs would be really useful. For example, if we could select a test folder (instead of just a file) and a reference folder then have it cycle through, taking the first file in the test folder, matching it to the first file in the reference folder and generate a LUT for each pair before moving on the the next pair.

Sure, it could take hours to run, but you could color match every shot in a reel automatically, and not have to sit there watching it, waiting to select the next pair of files. Just run it before you go to bed, and apply the LUTs in the morning.

TheStarWarsTrilogy.com.
The007Dossier.com.
Donations always welcome: Paypal | Bitcoin: bc1qzr9ejyfpzm9ea2dglfegxzt59tys3uwmj26ytj

Author
Time

Williarob said:

Dre, if you are planning to make some improvements… a way to batch jobs would be really useful. For example, if we could select a test folder (instead of just a file) and a reference folder then have it cycle through, taking the first file in the test folder, matching it to the first file in the reference folder and generate a LUT for each pair before moving on the the next pair.

Sure, it could take hours to run, but you could color match every shot in a reel automatically, and not have to sit there watching it, waiting to select the next pair of files. Just run it before you go to bed, and apply the LUTs in the morning.

This would be a brilliant upgrade and would truly elevate the tool’s efficiency. Of course, the tool is already amazing, so this would just be icing on the cake.

Author
Time
 (Edited)

I concur. Batch processing would be icing on the cake; making your great program that much better.

Author
Time

I will have a look, whether I can cook up something…😉

Author
Time

DrDre said:

I will have a look, whether I can cook up something…😉

Perhaps you supply the file pairs via a csv?

That way you don’t have to worry about the order and it would be quick a painless for the user to generate such a list.

Save London’s Curzon Soho Cinema

Author
Time

i would prefer a commandline version myself but am greatful for whatever you give us. Thanks for the awesome tool.

Author
Time
 (Edited)

oohteedee said:

i would prefer a commandline version myself but am greatful for whatever you give us. Thanks for the awesome tool.

Yes! That may even be better. It would be easy to create a batch file to run as many matches as needed back to back, plus each one could have different settings. e.g.:

// colormatch.bat:
colormatch -t test_01.tif -r reference_01.tif -o match_01.LUT -cs 50 -s 0.05
colormatch -t test_02.tif -r reference_02.tif -o match_02.LUT -cs 10 -s 0.01

TheStarWarsTrilogy.com.
The007Dossier.com.
Donations always welcome: Paypal | Bitcoin: bc1qzr9ejyfpzm9ea2dglfegxzt59tys3uwmj26ytj

Author
Time
 (Edited)

alexp120 said:

lansing said:

DrDre said:

lansing said:

DrDre said:

lansing said:

DrDre said:

It’s generally much faster to export a LUT for use in Davinci Resolve or Adobe After Effects, than to do it frame by frame in the tool. Shot-by-shot correction still takes a lot of time though, as each LUT is good for roughly 100 frames, and there are roughly 2,000 shots in a two hour film.

Thanks, I imported the generated LUT into Premiere and it applied instantly, with the cost of spike in RAM.

I’m testing it out on my dragon ball now, and I have a panning shot where there’re noticeable ringing artifacts along the lines. I have to turn smooth up to 0.9 in order to get it away. Is this normal? Can you take a look? I uploaded the reference and test image.

reference: http://i.imgur.com/id8AiRx.png
test: http://i.imgur.com/I54GI7O.png

Did you make sure the cropping is the same for the test and reference frames? If so, could you also share the raw test frame?

I tested on 3 other scenes, they all work fine even without cropping. I did try cropping this test image to match the reference, but it’s still the same problem with the white ringing between the character and the sky. I also tried sampling from the last frame of this same scene and it works fine again without the need to pump up the smoothing parameter.

reference: http://i.imgur.com/YOCkH0E.png
test: http://i.imgur.com/sRUrxNw.png

The fact that it works without cropping is fortunate, but the method is not developed specifically assuming the image content is exactly the same, except for the colors. It may work fine for some frames, but give artifacts for others.

The reason you get ringing is, because the ringing is already present in the test frame, a side effect of DNR:

The ringing has rougly the same color as the clouds next to it, both being light blue.

The clouds in the reference image are more white, than in the test frame, while the sky is a darker blue:

By color matching the color of the clouds, you automatically also give the ringing rougly the same color as the clouds, causing them to be more apparent against the darker blue background. Sadly there’s very little that can be done about this.

By increasing the smoothing parameter, you reduce the color gradients, as the algorithm tries to keep the gradients as close to the original gradients as possible, while also trying to find the best color match. This may reduce the ringing somewhat, but will generally also result in a poorer color match.

Thanks for the explanation, so I think the best approach for this is to find a frame in the scene that has the least amount of ringing + covers a wide variety of colors, build a matching model out of it and apply it to the entire scene and hope for the best.

If you look at williarob’s “Restoring Color to Red Faded Film” video

http://thestarwarstrilogy.com/starwars/post/2016/09/12/Restoring-Color-to-a-Faded-Eastman-Print-of-Star-Wars

…beginning at the 15:47 mark, he explains how you can do just that–build a model containing a wide variety of colors. You are grabbing sample frames of the shot that you are working on from both the reference video and the test video, and creating LUT’s of all the colors in that shot.

I will see how effective the montage way goes, but where can I find this “color balancing” too?

Author
Time

I’ve got zero experience with command line versions, so I’m afraid that’s not very likely to happen.

The color balancing tool is not widely available.

Author
Time

alexp120 said:
If you look at williarob’s “Restoring Color to Red Faded Film” video

http://thestarwarstrilogy.com/starwars/post/2016/09/12/Restoring-Color-to-a-Faded-Eastman-Print-of-Star-Wars

…beginning at the 15:47 mark, he explains how you can build a model containing a wide variety of colors. You are grabbing sample frames of the shot that you are working on from both the reference video and the test video, and creating LUT’s of all the colors in that shot.

I noticed that the number of sample frames of the shot from both the reference video and the test video is 16. Why 16?

Author
Time

alexp120 said:

alexp120 said:
If you look at williarob’s “Restoring Color to Red Faded Film” video

http://thestarwarstrilogy.com/starwars/post/2016/09/12/Restoring-Color-to-a-Faded-Eastman-Print-of-Star-Wars

…beginning at the 15:47 mark, he explains how you can build a model containing a wide variety of colors. You are grabbing sample frames of the shot that you are working on from both the reference video and the test video, and creating LUT’s of all the colors in that shot.

I noticed that the number of sample frames of the shot from both the reference video and the test video is 16. Why 16?

I think it had to do with how big the montage image was going to be. I didn’t want any blank areas, so it had to be 4x4 or 3x3 or 5x5, but if I recall correctly, any bigger than 4x4 at that resolution (each frame about 848x360? - something like that) would just leave the color match tool hanging indefinitely on my system. Your system may be more or less powerful than mine, so your mileage may vary.

If you were using the tool to grade a film like Raiders or Star Wars then I would recommend you take 8 to 16 frames from every scene (rather than shot) and turn them into montages, one of the source (or test) frames and one of the target (reference) frames and create a LUT for each scene.

In my testing, I did try grabbing up to 64 small frames (smaller than SD) from an entire reel of Star Wars and generating montages and a single LUT for an entire reel, but found it was much less accurate than doing it on a scene by scene basis. However, this was probably because the reel did not have consistent colors (parts of the reel were scanned with different color settings) so 1 LUT to rule them all was not possible until all the shots had been color balanced first.

However you may be able to create a single montage for an entire episode of what you are working on, especially if the color changes are consistent.

TheStarWarsTrilogy.com.
The007Dossier.com.
Donations always welcome: Paypal | Bitcoin: bc1qzr9ejyfpzm9ea2dglfegxzt59tys3uwmj26ytj

Author
Time

This question likely comes from a lack of understanding of the technology, but could this same mechanic be used as a means of super sampling/upscaling?

For example, say you used a GOUT frame as a source and a 70mm frame as a reference (both would be the same frame of course). Could you theoretically use an algorithm to create an upscaling script that would match the detail and idiosyncracies of the higher quality source as best as possible?

Seeking only the most natural looking colors for Star Wars '77

Author
Time

Williarob said:

alexp120 said:

alexp120 said:
If you look at williarob’s “Restoring Color to Red Faded Film” video

http://thestarwarstrilogy.com/starwars/post/2016/09/12/Restoring-Color-to-a-Faded-Eastman-Print-of-Star-Wars

…beginning at the 15:47 mark, he explains how you can build a model containing a wide variety of colors. You are grabbing sample frames of the shot that you are working on from both the reference video and the test video, and creating LUT’s of all the colors in that shot.

I noticed that the number of sample frames of the shot from both the reference video and the test video is 16. Why 16?

I think it had to do with how big the montage image was going to be. I didn’t want any blank areas, so it had to be 4x4 or 3x3 or 5x5, but if I recall correctly, any bigger than 4x4 at that resolution (each frame about 848x360? - something like that) would just leave the color match tool hanging indefinitely on my system. Your system may be more or less powerful than mine, so your mileage may vary.

If you were using the tool to grade a film like Raiders or Star Wars then I would recommend you take 8 to 16 frames from every scene (rather than shot) and turn them into montages, one of the source (or test) frames and one of the target (reference) frames and create a LUT for each scene.

In my testing, I did try grabbing up to 64 small frames (smaller than SD) from an entire reel of Star Wars and generating montages and a single LUT for an entire reel, but found it was much less accurate than doing it on a scene by scene basis. However, this was probably because the reel did not have consistent colors (parts of the reel were scanned with different color settings) so 1 LUT to rule them all was not possible until all the shots had been color balanced first.

However you may be able to create a single montage for an entire episode of what you are working on, especially if the color changes are consistent.

This is a very late follow up because I was slacking off. I created a montage reference image and it sure is more accurate. My question now is is 4x4 montage the overall best size as a reference for a scene? Or is it better to build the montage with 1 frame from each second in the scene?

My second question is what is the minimum resolution we can use to create the montage without affecting quality when building the color matching model in the program? It sounds too crazy to build the montage with the full size 1920x1080 frames.

Author
Time

lansing said:

Williarob said:

alexp120 said:

alexp120 said:
If you look at williarob’s “Restoring Color to Red Faded Film” video

http://thestarwarstrilogy.com/starwars/post/2016/09/12/Restoring-Color-to-a-Faded-Eastman-Print-of-Star-Wars

…beginning at the 15:47 mark, he explains how you can build a model containing a wide variety of colors. You are grabbing sample frames of the shot that you are working on from both the reference video and the test video, and creating LUT’s of all the colors in that shot.

I noticed that the number of sample frames of the shot from both the reference video and the test video is 16. Why 16?

I think it had to do with how big the montage image was going to be. I didn’t want any blank areas, so it had to be 4x4 or 3x3 or 5x5, but if I recall correctly, any bigger than 4x4 at that resolution (each frame about 848x360? - something like that) would just leave the color match tool hanging indefinitely on my system. Your system may be more or less powerful than mine, so your mileage may vary.

If you were using the tool to grade a film like Raiders or Star Wars then I would recommend you take 8 to 16 frames from every scene (rather than shot) and turn them into montages, one of the source (or test) frames and one of the target (reference) frames and create a LUT for each scene.

In my testing, I did try grabbing up to 64 small frames (smaller than SD) from an entire reel of Star Wars and generating montages and a single LUT for an entire reel, but found it was much less accurate than doing it on a scene by scene basis. However, this was probably because the reel did not have consistent colors (parts of the reel were scanned with different color settings) so 1 LUT to rule them all was not possible until all the shots had been color balanced first.

However you may be able to create a single montage for an entire episode of what you are working on, especially if the color changes are consistent.

This is a very late follow up because I was slacking off. I created a montage reference image and it sure is more accurate. My question now is is 4x4 montage the overall best size as a reference for a scene? Or is it better to build the montage with 1 frame from each second in the scene?

My second question is what is the minimum resolution we can use to create the montage without affecting quality when building the color matching model in the program? It sounds too crazy to build the montage with the full size 1920x1080 frames.

Montages will work, but the more frames the more difficult it is to match the frames, with a higher probability of artifacts. For the fast mode the frame size is significantly reduced.

Author
Time

DrDre said:

lansing said:

Williarob said:

alexp120 said:

alexp120 said:
If you look at williarob’s “Restoring Color to Red Faded Film” video

http://thestarwarstrilogy.com/starwars/post/2016/09/12/Restoring-Color-to-a-Faded-Eastman-Print-of-Star-Wars

…beginning at the 15:47 mark, he explains how you can build a model containing a wide variety of colors. You are grabbing sample frames of the shot that you are working on from both the reference video and the test video, and creating LUT’s of all the colors in that shot.

I noticed that the number of sample frames of the shot from both the reference video and the test video is 16. Why 16?

I think it had to do with how big the montage image was going to be. I didn’t want any blank areas, so it had to be 4x4 or 3x3 or 5x5, but if I recall correctly, any bigger than 4x4 at that resolution (each frame about 848x360? - something like that) would just leave the color match tool hanging indefinitely on my system. Your system may be more or less powerful than mine, so your mileage may vary.

If you were using the tool to grade a film like Raiders or Star Wars then I would recommend you take 8 to 16 frames from every scene (rather than shot) and turn them into montages, one of the source (or test) frames and one of the target (reference) frames and create a LUT for each scene.

In my testing, I did try grabbing up to 64 small frames (smaller than SD) from an entire reel of Star Wars and generating montages and a single LUT for an entire reel, but found it was much less accurate than doing it on a scene by scene basis. However, this was probably because the reel did not have consistent colors (parts of the reel were scanned with different color settings) so 1 LUT to rule them all was not possible until all the shots had been color balanced first.

However you may be able to create a single montage for an entire episode of what you are working on, especially if the color changes are consistent.

This is a very late follow up because I was slacking off. I created a montage reference image and it sure is more accurate. My question now is is 4x4 montage the overall best size as a reference for a scene? Or is it better to build the montage with 1 frame from each second in the scene?

My second question is what is the minimum resolution we can use to create the montage without affecting quality when building the color matching model in the program? It sounds too crazy to build the montage with the full size 1920x1080 frames.

Montages will work, but the more frames the more difficult it is to match the frames, with a higher probability of artifacts. For the fast mode the frame size is significantly reduced.

For making a montage, what is a good size for any individual frame to reduce to? Because it makes sense to reduce a 4x4 montage of 1920x1080 frames, but it doesn’t make sense to reduce the size of a 4x4 montage that is 1920x1080, since each frame inside the montage is very small already.

Author
Time

Williarob said:

Dre, if you are planning to make some improvements… a way to batch jobs would be really useful. For example, if we could select a test folder (instead of just a file) and a reference folder then have it cycle through, taking the first file in the test folder, matching it to the first file in the reference folder and generate a LUT for each pair before moving on the the next pair.

Sure, it could take hours to run, but you could color match every shot in a reel automatically, and not have to sit there watching it, waiting to select the next pair of files. Just run it before you go to bed, and apply the LUTs in the morning.

I came here to ask for nearly the same thing and see that it was already posted. I would love to be able to set up two folders with perfectly aligned and cropped frames to figure out the color correction and a third folder with the frames to apply the color correction to. I have a 4:3 source and a 16:9 source that I will use a photoshop script to align and crop into two folders for the color correction program. Having to manually color correct each frame would take forever, but currently due to the dynamic color, doing only a few frames at a time produces good results. Having a way to set up three folders (color reference frame, color target frame, frame to apply it to) with filenames that match would be great (0001.bmp, 0002.bmp, etc.) and a fourth corrected output folder. A whole movie could be automated with perfect color correction if the frames were always aligned the same way.

If you could create this, it would be great! Thanks for your consideration.

Author
Time

So I did a result comparison between LUTs created by the original 1080p size, a shrank 720p, and by using the “fast processing mode” in the program on my anime. And I saw noticeable differences in the light areas on the intended “faster” methods compare to the LUT created from the original size. So in my conclusion, don’t resize or use the “fast processing mode” if you’re going for quality, because the visual differences are not neglectable.

Author
Time

I ran into a problem with RAM usage exceeding 4G. I was doing a color match on two 7680x3240 montage and the process just killed itself once it exceeded 4G of RAM usage. Can you add a 64 bit version of the program?

Author
Time

lansing said:

I ran into a problem with RAM usage exceeding 4G. I was doing a color match on two 7680x3240 montage and the process just killed itself once it exceeded 4G of RAM usage. Can you add a 64 bit version of the program?

Sadly I only have a 32 bit version of MATLAB that is able to compile the software.

Author
Time

Williarob said:

I think I have access to 64 bit version of Matlab - and a mac version.

You also need the MATLAB compiler. Do you have it?

Author
Time

Excellent, I will send you the code later today. 😃

Author
Time

Williarob said:

I think I have access to 64 bit version of Matlab - and a mac version.

A Mac version would be awesome, if doable. Right now I have to use VMWare to use it.