Generating scenes containing shadows using pixel noise reduction techniques

Inventors

Story, Jon

Assignees

Nvidia Corp • Tamr Inc

Abstract

The disclosure presents a technique for utilizing ray tracing to produce high quality visual scenes with shadows while minimizing computing costs. The disclosed technique can lower the number of rays needed for shadow region rendering and still maintain a targeted visual quality for the scene. In one example, a method for denoising a ray traced scene is disclosed that includes: (1) applying a pixel mask to a data structure of data from the scene, wherein the applying uses the scene at full resolution and pixels at the edge of a depth boundary change are identified using the pixel mask, (2) generating a penumbra mask using the data structure, (3) adjusting HitT values in the packed data buffer utilizing the penumbra mask, and (4) denoising the scene by reducing scene noise in the data of the data structure with adjusted HitT values.

Core Innovation

The invention provides a denoising ray traced shadows technique (DRTS) for denoising a ray traced image of a scene. The method applies a pixel mask to scene data using the scene at full resolution, then generates a penumbra mask using the scene data and one or more pixels at an edge of a depth boundary change identified using the pixel mask.

The method adjusts hit distance (HitT) values to a set of pixels of the scene data that are identified by the penumbra mask. After HitT adjustment, the method denoises the scene by reducing scene noise in the scene data with the adjusted HitT values.

The technique includes generating a complex pixel mask from depth boundary changes at full resolution, identifying edge pixels at depth boundary changes using the pixel mask, and applying a penumbra mask epsilon test in some instances. It also refines HitT adjustment to support shadow-region behavior, including smoothing HitT values and using HitT neighborhood processing conditioned on the penumbra mask.

The technique addresses overlapping-penumbra behavior by applying a minimum HitT value within a HitT radius when adjusting HitT values. It generates a final shadow mask that resolves complex pixels using depth-boundary-aware searches, and uses the final shadow mask in a renderer that generates a frame of the scene utilizing ray tracing.

Claims Coverage

This patent includes three independent claims (a method claim, a system claim, and a rendering system claim) that collectively cover applying a full-resolution pixel mask, generating a penumbra mask from depth boundary change edge pixels, adjusting HitT for penumbra-indicated pixels, denoising by reducing scene noise using adjusted HitT, and generating and using a final shadow mask for ray-traced rendering. Across the independent claims, the inventive features center on pixel and penumbra mask generation tied to depth boundary change and HitT adjustment driving denoising, with rendering integration via a final shadow mask.

The independent claims require a pipeline where full-resolution pixel masking identifies depth boundary change edge pixels, a penumbra mask is generated from those pixels, HitT values are adjusted for the penumbra-indicated pixels, and denoising reduces scene noise using the adjusted HitT values; in the rendering system, this culminates in generating a final shadow mask used for ray-traced frame generation.

Stated Advantages

Documented Applications