What is the maximum resulution I can use effects and stuff without my images getting all screwed up?

[Cheeseman]

I am attempting to make a composite image of London from google maps data. The resolution is 40000*24000, and if I apply any effect, even as simple as sharpen, the image becomes... this https://imgur.com/a/uIsb3f0

 

It makes the image into giant strips of pixels, and doesnt apply the effect?

 

Only when applying effects to 200 megapixel+ images or so it bugs out.

 

Is there any fix, is it hardware, or software? (using pdn 5.0.3 beta, manual download, 64bit windows 10) (rx 6900xt + ryzen 5 5600x + 64gb ram)

[Rick Brewster]

This sounds like a GPU driver bug. Running Sharpen on a 40K x 24K image works perfectly fine for me on a GeForce 4090.

 

Make sure your GPU drivers are up-to-date. Make sure you are completely caught up on Windows Updates.

 

Also, are you sure you're on 5.0.3 beta? The latest beta is for 5.0.4.

 

In a pinch, you can go into the app settings (gear icon at top right of main window), then Graphics, and then change the "rendering device" to the CPU. In general this is a very bad thing to do because the CPU is extremely slow for rendering many effects (esp. distortion effects). So you should only do this temporarily when/if you need it.

 

[Cheeseman]

Ah thanks, the usual... Just amd things. The only thing stopping me from doing anything complicated just <No cursing.>ing amd things. No stable diffusion, no complicated random video game shader modding, no super high res images. I guess thats what I get when trying to save money.

[toe_head2001]

I just tried this with my RX 6600. Can confirm the issue.

Definitely a driver bug when the image resolution is high enough.

 

I'm not sure if this a new bug with the latest Radeon driver, as I never tried using such a large image before.

I will do some version bisecting over the weekend... to satisfy my curiosity.

[Rick Brewster]

Confirmed on a Radeon PRO W6400 as well.

 

Strangely, does not happen with the Ryzen 7000's iGPU, also a Radeon.

[Rick Brewster]

Also, it's all GPU-based effects and adjustments that don't work correctly. Not just Sharpen.

 

Move Selected Pixels is also affected.

[Rick Brewster]

Works fine on a Ryzen 5700G.

 

So it would seem this affects AMD's dGPUs but not iGPUs.

[Rick Brewster]

The cutoff seems to be 16,384 pixels -- if I resize an image to be 16384px wide, it's fine. At 16385+ px, it starts showing problems.

 

Portion of image I started with:

 

After resizing the whole image to 16,385 pixels wide (w/ Maintain Aspect Ratio) and then doing a tiny rotation with Move Selected Pixels:

 

 

 

Snapping the rotation back to 0 degrees shows issues at the right edge, and also in the middle around the 8192 px mark:

 

Conclusion: There's an issue getting the bitmap data onto the GPU. Once it's there, the pixel shaders are working fine, but they're operating on broken pixel data.

 

This is on a Radeon Pro W6400. Switching to the Ryzen 7950X's built-in iGPU works fine. Switching to GeForce 4090 also works fine, as expected.

[Rick Brewster]

You might have some luck if you report this bug to AMD using their Bug Report Tool:

 

https://www.amd.com/en/support/kb/faq/amdbrt

 

I just submitted a bug report, but this probably has a better chance of being fixed if more people report it.

[toe_head2001]

I did some bisecting this afternoon. It's been broken for approximately 1 year.

 

Working: 22.4.1 (April 5, 2022)

Broken: 22.5.2 (May 23, 2022)

 

(there a few minor releases between these two versions that can be bisected further, but I just used what was already in my Downloads folder)

 

 

I also submitted a bug report to AMD.

[Rick Brewster]

I was able to get a report from someone with a 7900XT: yup, happens there too

[Rick Brewster]

BTW an update on this: AMD is aware of the bug. I spoke to someone who works there about it. That's about as much as I know at this point though -- I don't know when this will be fixed (or if, but let's not get cynical just yet!).

[Rick Brewster]

According to @toe_head2001, this no longer repros with the latest driver, currently 23.12.1 WHQL. So it was fixed sometime in the last 5 1/2 months!