AMaZE not working right??

[ilia3101]

Compare MLV App with amaze and bilinear:

AMaZE	bilinear

You can see amount of colour artifacts increases!!! ...or at least doesn't decrease

Now look at MLRawViewer amaze vs bilinear:

AMaZE	bilinear

Artifacts of colour are reduced.

What might be wrong?
I have had this suspicion for such a long time, but MLRawViewer really pointed it out to me today.

[bouncyball-git]

You mean AMaZE artifacts are less in mlrawviewer and it's opposite in mlvapp right?

[bouncyball-git]

I've been also thinking about it all the time from the beginning. I have no any idea why it's wrong though :(

[masc4ii]

Same for my clip:
MLV App:

MlRawViewer:

None of these cyan edges on the water is present.

[masc4ii]

One more thing: with saturation full right, these stripes are a very light cyan. With saturation full left (b&w), this are dark lines (see on the water, switch between the pics in tabs):

[bouncyball-git]

In mlrawviewer use srgb or re709 for comparison with mlv app, not og space as you both did :)

btw exactly what color space we observing in the player of mlv app?

[masc4ii]

I uploaded a short version of the clip for you to test:
Download1
And another one with so nice moiree...:
Download2

[ilia3101]

thanks for the clips :)

@bouncyball-git I found the 'HDR' mode in MLRawViewer was almost the same as MLV App's default tonemapped profile, so I did a direct comparison, tried to match them a bit:

Still clearly shows a difference.
As for what colour space MLV App uses or is, well that's still a mystery, though it is being treated as rec709 by ffmpeg, so we could probably think of it as rec709 for now, until we get it figured out a little better. I think it is also being displayed as rec709 (or maybe just the display's native values, but that should be approximate to rec709 on most good screens).. not 100% sure what the Qt display widget is doing. I was going to add an option where the user can specify what colour space their screen is most close to, so it can be output correctly for the screen. That will probably be coming with the planned colour management stuff.

[bouncyball-git]

I always dreamed to use OpenColorIO for color management of my future application ;) now I can say "for our cutest MLV App".

[bouncyball-git]

As for the images above: YES ugly artifacts are there and we have to understand why.

[masc4ii]

It comes not from the processing. I disabled processing, exported a PNG and tried to process with another image tool. The artefacts are the same.

[ilia3101]

OpenColourIO is worth looking at. Maybe will come to MLV App 😉

Who might know about how to fix this issue? Is there someone on the magic lantern forum who knows about this kind of thing? I really wish this could just get fixed already.

[bouncyball-git]

We should ask there :)

[DeafEyeJedi]

OpenColorIO would indeed be amazing to have it built in within the app. Seems like a long shot and shouldn’t be a priority while in this stage. Though I can totally see/feel this one coming...

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On Nov 19, 2017, at 10:11 AM, Ilia Sibiryakov ***@***.***> wrote: OpenColourIO is worth looking at. Maybe will come to MLV App 😉 Who might know about how to fix this issue? Is there someone on the magic lantern forum who knows about this kind of thing? I really wish this could just get fixed already. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or mute the thread.

[bouncyball-git]

Yeah, we need to sort out the quality of the AMaZE debayerer first.

[ilia3101]

http://www.magiclantern.fm/forum/index.php?topic=20995.msg193416#msg193416
Asked a1ex, suggestion is to try white balancing the image before AMaZE. If it works well, I'll add some kind of channel equalizing during the demosaic (and of course reset after to not ruin processing).

[bouncyball-git]

Hmm.. iunteresting how to apply WB (matrix?) to the bayered data. Is it done during normalization?

[masc4ii]

Hm... don't know if that is the reason. If I comment out WB, I would then expect a picture with wrong colors, but without artefacts.
I commented the WB+exposure part out: The colors are wrong (okay), but the artefacts are still there.
Or was it wrong what I thought? EDIT: or do the artefact go away by doing some WB on the bayered data?!

[bouncyball-git]

I dug into darktable's related code today, it's pure C and source is huge, OpenCL is used all over there for image processing and matrix applying. AMaZE is CPU based thought and works fantastic. If I switch WB off in the interface then greenesh familiar debayered unprocessed look appears on the screen and small aliasing artifacts can be seen on the edges (almos exactly like on our mlv app with processing object wholly disabled). After turning WB on in darktabe aliasing is almost gone even when sharpening is applied.

[ilia3101]

No, it shouldn't be a matrix, as there's no way to blend the channels, just increase the value of red/blue pixels or decrease the green to get them equalised. I'll show what the results are soon.

[ilia3101]

I'll try and put it right in to the AMaZE demosaic() function.

[ilia3101]

Comment inside AMaZE seems to confirm the theory:

[ilia3101]

Apologies for the years of bad AMaZE.

6ed7e00 seems to have improved it.
Up next: automatic multiplier generation within AMaZE for even better channel balance.

Please try it out @masc4ii masc and see if its still worse than MLRawViewer on your clips

[masc4ii]

WOW! I am impressed! Congratulations! This is so much better, also with my other clips!

[ilia3101]

maybe I'll leave this issue open for a little bit until I get the multipliers automated, as currently its most optimal for daytime white balance.

[masc4ii]

I am still impressed and AMaZEd!!! This difference is unbelievable!
Before:

After:

You made me really happy today! :-) Now the results with my files are better than with Resolve.

[ilia3101]

Wow that's a great difference!!! Many shots will be saved. I was beginning to think that the 5D2 is completely doomed every time I used MLV App, but now that feeling will finally disappear :)

[bouncyball-git]

Hey fantastic! I IS A REAL AMAZE!!! Hahaha I feel so better now too! :-D

[bouncyball-git]

Before

After

[bouncyball-git]

GREAT!

Uhm... Can it be tuned little bit more? :P

[masc4ii]

I had to play around with the new version... sry for that :-)

Uploaded in 4K, but youtube knows even then how to crush the quality, hehe.
Edit: still not perfect, but way better than youtube:
https://vimeo.com/244015087

[bouncyball-git]

@ilia3101

Ни как не нарадуюсь как хорошо работает подлеченный AMaZE :-D. Спасибо!