Methods and systems for direct-to-indirect acoustic radiance transfer

1. A method for simulating sound propagation within a scene, the method comprising:

pre-computing a transfer operator for simulating results of sound reflection within a modeled scene;

simulating distribution of sound energy from a sound source positioned within the scene;

applying the transfer operator to the distribution of sound energy from the sound source to compute simulated sound at a plurality of points within the scene; and

simulating collection of sound energy from the plurality of points within the scene to a listener positioned within the scene.

2. The method of claim 1 , wherein pre-computing a transfer operator comprises mapping surfaces of the modeled scene to the plurality of points.

3. The method of claim 1 , wherein pre-computing a transfer operator comprises forming a matrix of time-varying impulse responses at each of the plurality of points within the scene.

4. The method of claim 3 , wherein forming a matrix of time-varying impulse responses comprises forming a matrix of impulse responses corresponding to a single diffuse reflection.

5. The method of claim 3 , wherein forming a matrix of time-varying impulse responses comprises forming a matrix of impulse responses corresponding to multiple diffuse reflections.

6. The method of claim 3 , wherein pre-computing a transfer operator comprises determining a singular value decomposition of the matrix of impulse responses.

7. The method of claim 3 , wherein pre-computing a transfer operator comprises deriving a Karhunen-Loeve Transform basis matrix from the matrix of impulse responses.

8. The method of claim 1 , wherein simulating distribution of sound energy from a sound source positioned within the scene comprises determining a direct impulse response to the sound source at each of the plurality of points within the scene.

9. The method of claim 8 , wherein determining a direct impulse response to the sound source at each of the plurality of points within the scene comprises applying an interactive ray tracing technique to compute a direct impulse response at each of the plurality of points.

10. The method of claim 8 , wherein applying the transfer operator to the simulated distribution of sound energy within the scene comprises computing an indirect impulse response at each of the plurality of points within the scene based on the direct impulse responses.

11. The method of claim 9 , comprising applying the transfer operator a predetermined number of times to the simulated distribution of sound energy within the scene to compute an indirect impulse response at each of the plurality of points within the scene based on multiple reflections of the direct impulse responses.

12. The method of claim 1 , wherein one or both of the sound source or the listener are moving.

13. The method of claim 1 , comprising:

computing reflections and edge diffractions of the distribution of sound energy from a sound source using path tracing to simulate an early response to the distribution of sound energy;

wherein applying the transfer operator to compute simulated sound at the plurality of points comprises simulating a late response to the distribution of sound energy; and

wherein simulating collection of sound energy from the plurality of points comprises combining the early response and the late response.

14. A non-transitory computer readable medium having stored thereon executable instructions that when executed by a processor of a computer control the computer to perform steps comprising:

pre-computing a transfer operator for simulating results of sound reflection within a modeled scene;

simulating distribution of sound energy from a sound source positioned within the scene;

applying the transfer operator to the distribution of sound energy from the sound source to compute simulated sound at a plurality of points within the scene; and

simulating collection of sound energy from the plurality of points within the scene to a listener positioned within the scene.

15. The computer readable medium of claim 13 , wherein pre-computing a transfer operator comprises forming a matrix of time-varying impulse responses at each of the plurality of points within the scene.

16. The computer readable medium of claim 15 , wherein pre-computing a transfer operator comprises determining a singular value decomposition of the matrix of impulse responses.

17. The computer readable medium of claim 15 , wherein pre-computing a transfer operator comprises deriving a Karhunen-Loeve Transform basis matrix from the matrix of impulse responses.

18. A system for simulating sound propagation within a scene, the system comprising:

a transfer operator embodied in a non-transitory computer readable medium for simulating results of sound reflection within a scene; and

a sound simulator for receiving as input a distribution of sound energy from a sound source positioned within a scene and for applying the transfer operator to the distribution of sound energy from the sound source to compute simulated sound at a plurality of points within the scene.

19. The system of claim 18 , wherein the transfer operator comprises a matrix of time-varying impulse responses at each of the plurality of points within the scene.

20. The system of claim 18 , wherein the transfer operator comprises a singular value decomposition of a matrix of time-varying impulse responses at each of the plurality of points within the scene.

21. The system of claim 18 , wherein the transfer operator comprises a Karhunen-Loeve Transform basis matrix derived from a matrix of time-varying impulse responses at each of the plurality of points within the scene.