OptiX denoising at high resolutions causes artifacts #92308

New Issue

Alaska · 2021-10-18T10:51:35+02:00

Alaska commented

2021-10-18 10:51:35 +02:00

System Information:
Operating system: Linux-5.14.0-2-amd64-x86_64-with-glibc2.33 64 Bits
Graphics card: NVIDIA GeForce RTX 3090/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 470.63.01

Blender Version:
Broken: version: 3.0.0 Alpha, branch: master, commit date: 2021-10-18 07:42, hash: 4f3f79c382
Worked: Unsure

Short description of error:
With OptiX denoising enabled and rendering a scene at a high resolution, some artifacts can occur with the denoising.


Denoising result	Render before denoising

Exact steps for others to reproduce the error:

Create a scene in Cycles that's quick to render (decrease the sample count to 1 for fast rendering).
Enabled OptiX denoising for the final render.
Increase the render resolution to something large (7680x4320 in my case)
Render the scene. You will notice the final render appears broken after denoising.

**System Information:** Operating system: Linux-5.14.0-2-amd64-x86_64-with-glibc2.33 64 Bits Graphics card: NVIDIA GeForce RTX 3090/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 470.63.01 **Blender Version:** Broken: version: 3.0.0 Alpha, branch: master, commit date: 2021-10-18 07:42, hash: `4f3f79c382` Worked: Unsure **Short description of error:** With OptiX denoising enabled and rendering a scene at a high resolution, some artifacts can occur with the denoising. |![OptiX broken.png](https://archive.blender.org/developer/F11240482/OptiX_broken.png)|![Expected.png](https://archive.blender.org/developer/F11240490/Expected.png)| | -- | -- | |Denoising result|Render before denoising| **Exact steps for others to reproduce the error:** 1. Create a scene in Cycles that's quick to render (decrease the sample count to 1 for fast rendering). 2. Enabled `OptiX` denoising for the final render. 3. Increase the render resolution to something large (7680x4320 in my case) 4. Render the scene. You will notice the final render appears broken after denoising.

Alaska commented

2021-10-18 10:51:35 +02:00

Added subscriber: @Alaska

Germano Cavalcante commented

2021-10-21 18:52:35 +02:00

Added subscribers: @iss, @mano-wii

Germano Cavalcante commented

2021-10-21 18:52:35 +02:00

Thanks for the report.
I don't have access to NVIDIA GPU at the moment.
@iss, can you reproduce this issue?

Thanks for the report. I don't have access to NVIDIA GPU at the moment. @iss, can you reproduce this issue?

Richard Antalik commented

2021-10-26 02:48:26 +02:00

Can't reproduce, got quite clear looking cube.

System Information
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 3060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 472.12

Can't reproduce, got quite clear looking cube. **System Information** Operating system: Windows-10-10.0.19041-SP0 64 Bits Graphics card: NVIDIA GeForce RTX 3060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 472.12

Alaska commented

2021-10-26 03:50:39 +02:00

It's possible this is a Linux only issue. I will retest on Windows 11 and report back with results.

It should be noted that there are issues with OptiX denoising at all resolutions on Linux if Nvidia driver 495.29.05 is used #92472 (OptiX denoising artifacts with recent GPU driver 495.29.05 or newer on Linux). Patrick Mours of Nvidia was going to take a look at it.

It's possible this is a Linux only issue. I will retest on Windows 11 and report back with results. It should be noted that there are issues with OptiX denoising at all resolutions on Linux if Nvidia driver 495.29.05 is used #92472 (OptiX denoising artifacts with recent GPU driver 495.29.05 or newer on Linux). Patrick Mours of Nvidia was going to take a look at it.

Alaska commented

2021-10-26 04:24:17 +02:00

Testing on Windows at a resolution of 7680 x 4320 there were no issues. Testing at a higher resolution (15360 x 8640) the render turns completely black after denoising.

System Information
Operating system: Windows-10-10.0.22000-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 3090/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 496.13
Blender version: 3.0.0 Alpha, branch: master, commit date: 2021-10-25 23:16, hash: 32cc9ff037

Testing on Windows at a resolution of 7680 x 4320 there were no issues. Testing at a higher resolution (15360 x 8640) the render turns completely black after denoising. **System Information** Operating system: Windows-10-10.0.22000-SP0 64 Bits Graphics card: NVIDIA GeForce RTX 3090/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 496.13 Blender version: 3.0.0 Alpha, branch: master, commit date: 2021-10-25 23:16, hash: `32cc9ff037`

Richard Antalik commented

2021-10-26 04:34:43 +02:00

I can confirm black image with very high resolution after denoising.

Brecht Van Lommel commented

2021-11-18 15:03:59 +01:00

Added subscribers: @pmoursnv, @brecht

Brecht Van Lommel commented

2021-11-18 15:03:59 +01:00

CC @pmoursnv.

Patrick Mours commented

2021-11-18 16:53:38 +01:00

The corrupted result @Alaska is seeing was a driver bug that has since been fixed. Updating to driver 472.12 or newer on Windows or 470.74 or newer on Linux solves this (470.63 still shows it).

The OptiX denoiser does have an upper limit as to how many pixels it can denoise at once apart from that. optixDenoiserComputeMemoryResources returns OPTIX_ERROR_INVALID_VALUE when that limit is reached, but it looks like Cycles does not currently propagate that error back to the user (it shows up in the log though), which is why you are just getting a black image at very high resolutions.
There is a helper function in the OptiX SDK that splits a large image into smaller tiles and denoises them individually though, so could use that instead of just throwing an error (similar to how rendering is also split in tiles).

The corrupted result @Alaska is seeing was a driver bug that has since been fixed. Updating to driver 472.12 or newer on Windows or 470.74 or newer on Linux solves this (470.63 still shows it). The OptiX denoiser does have an upper limit as to how many pixels it can denoise at once apart from that. optixDenoiserComputeMemoryResources returns OPTIX_ERROR_INVALID_VALUE when that limit is reached, but it looks like Cycles does not currently propagate that error back to the user (it shows up in the log though), which is why you are just getting a black image at very high resolutions. There is a helper function in the OptiX SDK that splits a large image into smaller tiles and denoises them individually though, so could use that instead of just throwing an error (similar to how rendering is also split in tiles).

Brecht Van Lommel commented

2021-11-22 14:59:46 +01:00

It would be good to implement denoising in smaller tiles then, in a way that's invisible to the user.

It's probably simplest to implement this in the OptiX device. It could also be done at the level where we read back tiles from disk for denoising and reduce memory usage there by denoising in tiles, though not sure we should couple tile sizes there to OptiX limits.

It would be good to implement denoising in smaller tiles then, in a way that's invisible to the user. It's probably simplest to implement this in the OptiX device. It could also be done at the level where we read back tiles from disk for denoising and reduce memory usage there by denoising in tiles, though not sure we should couple tile sizes there to OptiX limits.

Brecht Van Lommel commented

2021-11-22 14:59:57 +01:00

Changed status from 'Needs Triage' to: 'Confirmed'