Left: without denoising. Right: using imager_denoiser_oidn. The Oidn denoiser (based on Intel's Open Image Denoise technology) is available as a post-processing effect. It is integrated into Arnold for use with IPR as an imager (so that you get a very quickly denoised image as you're moving the camera and making other adjustments).
Common
Enable
Enables the imager.
Layer Selection
Enables the imager.
Parameters
Output Suffix
When set, creates a new additional output with the input name plus the suffix in which the denoised result will be written into. For example, when denoising the "RGBA" AOV with the output_suffix set to "_denoised", the denoised result will be written into a new "RGBA_denoised" output. It only works with multi-layer drivers.
Albedo
Optional albedo feature AOV is used to improve denoising quality (denoise_albedo_noisy is the default). Setting to an empty string "" will disable the use of feature AOVs, which might give better results when denoising AOVs for which no albedo exists.