Artifact Management in Clouds


I started to work on this image, harvested from spam, of all places, and headed for my wallpaper collection. I can crispen up the rocks satisfactorily. Unfortunately, when I scale up the image 4X, the clouds fill with artifacts from the AI overthinking the job.

I tried masking for the rocks and grass, hoping to constrain where sharpening happens, but no such luck.

My work-around is to feed the enlarged image to PhotoLab 6, and use Local Adjustments to blur the sky slightly, then use Sharpen AI to de-blur the results. It works, after a fashion.

Is there a better way to go at this task? Again, the task is to scale up 4X, sharpen the grass, rocks, and trees, while leaving the clouds artifact-free.

NOTE: I didn’t take this image. It was collected from unsolicited email. I make no claim of ownership or origination.

Is this what you are looking for?

The problem with TPAi seems to be the creations of artefacts along the horizon if denoising is applied in addition to upscaling

I ran the image through Gigapixel AI, which has far more controls, and this achieved a much better result, albeit without sharpening the rocks unduly:

You can download a free trail of GPAI but I suspect it places a watermark on the image.
I have uploaded it for you here:

The clouds seem to be artifact-free. What did you do to limit the artifacts?

(At the risk of seeming to look a gift horse in the mouth, the skyline edge, and the rocks, look …um… artificial.)

The original image, as harvested, has some color balance issues, and the blue sky needs to be tweaked a bit to get it closer to a plausible sky. All of that gets done with PhotoLab 6 (that is, outside of the scope of this forum).

In this sample, I used PL6 to handle contrast, lighting, color balance, and adjusted the sky color, and output to a TIFF. It went to Sharpen AI to clean up the rock texture, and recover the details in the trees on the skyline. I used masking to limit sharpening to the rocks and grass, leaving the sky, I hope, untouched. The TIFF output from Sharpen AI was then run through Gigapixel AI to scale up to 4X. It was run through PL6 again, this time with the clouds lightly blurred to smear the artifacts. I’d prefer to have artifact-free clouds instead.

Keep in mind that the original image is a 640 x 485 JPEG with an unknown degree of compression, which makes the job somewhat challenging. The amount of available data is somewhat limited(!).

For comparison purposes, this is the original JPEG run through PL6, but not yet processed through any Topaz apps.

Note the lack of detail in the trees slightly above and to the right of the center of the image. Likewise for the grasses and brush at the bottom of the cliff.

I took the image into Gigapixel to upscale x 4. Then into PaintShop Pro to separate the foreground from the background. Applied Gaussian Blur to soften the cloud layer, then sharpened the mountain layer. Finally recombined the layers and processed in Topaz Clarity.

You are correct about the artificial edge to the mountains. I should have softened them.

This is definitely the type of image where working on layers is a must.

Oh. In short, there was nothing done in Topaz Photo AI to protect the clouds?

You’re right, various forms of layering or localized processing can be used as work-arounds. The point of starting the thread was to determine whether I’d missed something when working within TPAI.

Correct, nothing was done in Topaz Photo AI.

Gotit - thanks for the “how you did it”, though. :slight_smile: