Adaptive polynomial rendering

Number: 9959664
Published: 2018-05-01
Filed: 2016-08-05
Assignee: Disney Enterprises, Inc.
Inventors: Moon; Bochang; Gross; Markus; McDonagh; Steven; Mitchell; Kenneth J.
CPC: G06T15/06
Verdict: Low Notable software
Source: Google Patents · FreePatentsOnline

The keeper's note

Adaptive polynomial rendering (grant dup).

Abstract

Embodiments can provide adaptive image filtering. Under this approach, image quality can be enhanced by adjusting an approximation function to better adapt image signals in different parts of an image. Certain parts of the image may be enhanced using a certain approximation function while some other parts of the image may be enhanced using a different approximation function. In certain embodiments, the approximation function selected for a part of the image can be a polynomial function having a specific order. The specific polynomial order can be applied directly to obtain an estimated image value of the part of the image. In certain embodiments, the estimation of the reconstruction error can include iteratively estimating a bias term of the reconstruction error and a variance term of the reconstruction error.

Background

BACKGROUND(1) Monte Carlo (MC) ray tracing is a rendering algorithm for synthesizing photo-realistic images from 3D models. MC rendering algorithm can typically be used to simulate a variety of rendering effects through a unified framework, i.e., ray tracing. The rendering time of MC ray tracing, however in many cases, is unacceptable since it typically requires integrating a huge number of ray samples, e.g., more than 10K ray samples per pixel, to generate a converged rendered image.(2) In attempting to tackle the aforementioned ray performance problem of MC ray tracing, various adaptive rendering techniques have been developed. Those techniques typically involve locally controlled sampling rate to adaptively adjust the image reconstruction. For example, some of those techniques involve adaptive sampling the heterogeneous noise property of rendered images to guide irregular sampling density rather than a uniform sampling, and locally controlling smoothing by considering MC noise so that high-frequency edges are properly preserved.(3) Adaptive image rendering has a long history. For example, Kajiya, J. T, in the paper entitled “the rendering equation” [ACM SIGGRAPH '86, 143-150], presented a general idea that high-dimensional MC samples can be allocated adaptively in a hierarchical structure by using the variances of the samples and these samples can be integrated to generate rendered images. Approaches using those techniques typically show high-quality rendering results for

Claims

1. A method for rendering an image from a three-dimensional model, the method being performed by a computer system and comprising: receiving the image obtained by ray tracing with the three-dimensional model; identifying one or more blocks of the image; for each block of the one or more blocks: for each Taylor polynomial function of a plurality of Taylor polynomial functions of different orders: estimating a reconstruction error for reconstructing the block of the image using the Taylor polynomial function; identifying one of the plurality of Taylor polynomial functions with a lowest estimated error; and reconstructing the block through the image filter using the identified Taylor polynomial function to obtain a filtered image block; and using the one or more filtered blocks to obtain a filtered image. 9. A system for rendering an image from a three-dimensional model, the system comprising one or more of a processors configured by machine-readable instructions to perform: receiving the image obtained by ray tracing with the three-dimensional model; identifying one or more blocks of the image; for each block of the one or more blocks: for each Taylor polynomial function of a plurality of Taylor polynomial functions of different orders: estimating a reconstruction error for reconstructing the block of the image using the Taylor polynomial function; identifying one of the plurality of Taylor polynomial functions with a lowest estimated error; and reconstructing the block through the image filter using the identified Taylor polynomial function to obtain a filtered image block; and using the one or more filtered blocks to obtain a filtered image. 17. A computer program product resident on a non-transitory tangible media that is executable on a computer system comprising a processor, a display, and a user-input device, the computer program product comprising: program code for receiving the image obtained by ray tracing with the three-dimensional model; program code for identifying one or more blocks of the image; for each block of the one or more blocks: for each Taylor polynomial function of a plurality of Taylor polynomial functions of different orders: program code for estimating a reconstruction error for reconstructing the block of the image using the Taylor polynomial function; program code for identifying one of the plurality of Taylor polynomial functions with a lowest estimated error; and program code for reconstructing the block through the image filter using the identified Taylor polynomial function to obtain a filtered image block; and program code for using the one or more filtered blocks to obtain a filtered image.