OptiX 7.7 Black tile blinking in the bottom left corner when using the denoiser

[Adhesive_Bagels]

I tried using the denoiser for my path tracing application but I get a black tile blinking in the bottom left corner of my denoised image. See this video I recorded.

I noticed that after a while, when my image starts to converge (and the beauty layer isn’t that noisy anymore), the tile isn’t there anymore (you can see it on the video that it blinks more just after moving the camera than after waiting for 2/3s). Also, when using a normal or albedo AOV, the tile is not there either.

I’m running an RTX 2060S with the Game Ready Driver 532.03.

I’m having the exact same issue with this sample from Ingo Wald’s Github OptiX7 course.

Where could it come from ?

[droettger]

Thanks for the report.
I could reproduce this with the example12_denoiseSeparateChannels from that repository and filed an internal bug report for investigation.

[droettger]

Please check if the OptixDenoiserOptions and OptixDenoiserParams inside your application are default initialized to zero.
That’s the recommended programming advice for all OptiX structures in case structures change among OptiX SDK versions.

The application must either provide valid device pointers in OptixDenoiserParams hdrIntensity AND hdrAverageColor OR set them to zero.

The OptixDenoiserParams data structure in the example12_denoiseSeparateChannels is missing the default initialization which is required when using newer OptiX SDKs than the one originally used when the examples were published.
The simplest fix and best programming practice for the example would be:

OptixDenoiserParams denoiserParams = {};  // in example12_denoiseSeparateChannels/SampleRenderer.cpp

[Adhesive_Bagels]

My OptixDenoiserParams was indeed uninitialized. Using OptixDenoiserParams = {} fixed it, thanks!