Residual ratio tracking for estimating attenuation in heterogeneous volumes

Number: 9767601
Published: 2017-09-19
Filed: 2014-11-19
Assignee: Disney Enterprises, Inc.
Inventors: Novak; Jan, Jarosz; Wojciech, Selle; Andrew
CPC: G06T15/506
Verdict: Low Notable software
Source: Google Patents · FreePatentsOnline

The keeper's note

A volumetric rendering technique that estimates light attenuation through heterogeneous media by tracking against a simplified fictitious medium.

Abstract

There is provided a system including a memory storing a software application and a processor configured to execute the software application to transmit a light through a scene, the scene including a medium described by an extinction function, define a fictitious medium described by a fictitious extinction function, determine a path through the medium, the path including a plurality of points, calculate one of a plurality of weights for each of the plurality of points, the one of the plurality of weights corresponding to one minus the ratio of the extinction function to the fictitious extinction function, and estimate a transmittance of the lights through the medium as a product of the plurality of weights.

Background

BRIEF DESCRIPTION OF THE DRAWINGS(1) FIG. 1 presents a system used for residual ratio tracking for estimating attenuation in heterogeneous volumes, according to one implementation of the present disclosure.(2) FIG. 2A presents an example of a heterogeneous medium, according to one implementation of the present disclosure.(3) FIG. 2B presents an example of using ratio tracking to calculate the transmittance of light through a heterogeneous participating medium, according to one implementation of the present disclosure.(4) FIG. 3 presents a graph illustrating the difference between estimating the transmittance through a participating medium using ratio tracking and the ground truth transmittance through the same participating medium, according to one implementation of the present disclosure.(5) FIG. 4A presents an example of an extinction function.(6) FIG. 4B presents an example of a fictitious extinction function for use with ratio tracking, according to one implementation of the present disclosure.(7) FIG. 4C presents an example of a control extinction function that is used to calculate the control transmittance for residual tracking, according to one implementation of the present disclosure.(8) FIG. 4D presents an example of a residual extinction function that is used tocalculate the residual transmittance for residual tracking, according to one implementation of the present disclosure.(9) FIG. 4E presents an example of a fictitious extinction function for use with residual

Claims

1. A device comprising: a display; a memory storing a software application; and a processor configured to execute the software application to: transmit light through a scene, the scene including a medium described by an extinction function; define a fictitious medium described by a fictitious extinction function; determine a path through the medium, the path including a pluralityof points; calculate one of a plurality of weights for each of the plurality of points, the one of the plurality of weights corresponding to one minus the ratio of the extinction function to the fictitious extinction function; estimate a transmittance of the light through the medium as a product of the plurality of weights; and render the scene, on the display, using the estimated transmittance of the light through the medium. 8. A device comprising: a display; a memory storing a software application; and a processor configured to execute the software application to: transmit light through a scene, the scene including a medium described by an extinction function; define a control medium described by a control extinction function; determine a control transmittance of the light through the medium based on the control extinction function; define a residual extinction function; determine a residual transmittance of the light through the medium based on the residual extinction function; estimate a transmittance of the light through the medium as the product of the control transmittance and the residual transmittance; and render the scene, on the display, using the estimated transmittance of the light through the medium. 14. A method for use by a device having a processor and a display for calculating a transmittance of light througha medium in a scene, the method comprising: transmitting, by the processor, the light through the scene, the scene including the medium described by an extinction function; defining, by the processor, a fictitious medium described by a fictitious extinction function; determining, by the processor, a path through the medium, the path including a plurality ofpoints; calculating, by the processor, one of a plurality of weights for each of the plurality of points, the one of the plurality of weights corresponding to one minus the ratio of the extinction function to the fictitious extinction function; estimating, by the processor, the transmittance of the light through the medium as a product of the plurality of weights; and rendering the scene, by the processor on the display, using the estimated transmittance of the light through the medium.