darktable-org
rotate and perspective highlight artefacts
Describe the bug
Strange highlight artefacts appear on some images if rotate and perspective is used to rotate the image.
Steps to reproduce
Download the raw and its XMP from http://tech.kovacs-telekes.org/files/2024-04-11-rotate-and-perspective-highlight-issues/, open it in the darkroom.
Select history entry 30:
Select history entry 31:
Affects both filmic and sigmoid (see history entry 33). With/without OpenCL. Zoomed-in view as well as zoomed out. The exported JPG is also affected.
Expected behavior
No response
Logfile | Screenshot | Screencast
No response
Commit
No response
Where did you obtain darktable from?
self compiled
darktable version
4.7.0+909~gcaa592293e
What OS are you using?
Linux
What is the version of your OS?
Ubuntu 23.10
Describe your system?
XOrg Ryzen 5 5600X, 64 GB RAM GTK 3.24.38 GCC 13.2.0
Are you using OpenCL GPU in darktable?
Yes
If yes, what is the GPU card and driver?
NVidia 1060 with 6 GB, driver 535.161.07 (the CPU path is also affected)
Please provide additional context if applicable. You can attach files too, but might need to rename to .txt or .zip
No response
@kofa73 the problem seems to be "somewhere else". First test show the artifacts are introduced in the first instance of D&S, seems be be related to a combination of a) feathering b) details threshold c) no-cropping in rotate&perspective. Will investigate further (btw i can see "feathering blocky artifacts" here, it helps to use darkroom/ui/develop_mask=TRUE to visualize this.
EDIT: i think i got it. Fix coming soon...
Even after the fix in above PR we still have a "strange looking" spot at that burned-out part. For those running into this issue, it's related to not-cropping in the rotate&perspective module. So we have the completely black border pretty close, that's affecting the guided filter.
Even after the fix in above PR we still have a "strange looking" spot at that burned-out part. For those running into this issue, it's related to not-cropping in the rotate&perspective module. So we have the completely black border pretty close, that's affecting the guided filter.
I am indeed seeing artifacts as of today. Is there a workaround? How is it "Fixed in master" when it is actually not?
Edit: okay - maybe actually unrelated. My problem occurs with rotate and perspective disabled as well. And it is only evident with high quality processing - which is why I only noticed it after a lengthy export. I will try to pin it down more and report back with more details.
Edit 2: Seems to be something different. My issues manifests with bumped up exposure (+2.5,+3 EV), vignetting correcion and filmic. Not present with sigmoid, but sigmoid doesn't seem to be suited for massively bumped exposure values. Unfortunately I can't share the source file but can provide screenshots if its helpful.
I tried to disable diffuse and sharpen, chromatic abberation correction, color equalizer, rotate and perspective and denoising, none of them seemed to have much impact..Only when disabling vignetting correct the issue was gone. It shows itself as white, feathery, smooth blobs in image corners.
@sans-c please open a "precise" & proper issue if you really think there is something wrong.