Generating image data

• US 6,487,322 B1
• Filed: 03/03/1999
• Issued: 11/26/2002
• Est. Priority Date: 03/03/1999
• Status: Expired due to Term

• Current Assignee: Autodesk, Inc.
• Original Assignee: Autodesk, Inc.
• Inventors: Bastos, Rui, Tampieri, Filippo
• Primary Examiner(s): Lee, Thomas D.
• Assistant Examiner(s): BRINICH, STEPHEN M
• Application Number:
  US09/261,146
• Time in Patent Office: 1,364 Days
• Field of Search: 382/274, 382/276, 382/254, 345/582-588, 358/1.9
• US Class Current: 382/274
• CPC Class Codes: G06T 15/50 Lighting effects

Abstract

A surface generated from a radiosity simulation is shaded. The surface is divided into a plurality of elements and a brightness value is calculated for each of the elements. An initial surface shading is defined in which the resolution of shading is determined in response to the highest element density of the surface. Element brightness values are processed to generate brightness values for the initial surface shading and values of the initial surface shading are filtered to generate brightness values for an enhanced surface shading. Brightness values of a plurality of elements may be combined to generate a single texel brightness value in the initial surface shading. The filtering step may include steps of increasing the resolution of the initial surface shading and filtering the increased resolution shading. A galcion filtering process may be performed.

Claims

1. A method of shading a surface generated from a radiosity simulation, in which said surface has been divided into a plurality of elements, and a brightness value has been calculated for each of said elements, including the steps of

defining an initial surface shading in which the resolution of shading is determined in response to the highest element density of said surface;

processing element brightness values to generate brightness values for said initial surface shading; and

filtering values of said initial surface shading to generate brightness values for an enhanced surface shading.

2. A method according to claim 1, wherein the resolution of said initial surface shading is equal to the density of one texture pixel (texel) per element vertex at the region of greatest element density within said surface generated from the radiosity simulation.

3. A method according to claim 1, wherein said step of processing element brightness values includes combining the brightness of a plurality of elements to generate a single texel brightness value in said initial surface shading.

4. A method according to claim 1 wherein said step of filtering includes the steps of

increasing the resolution of said initial surface shading; and

filtering said increased resolution shading.

5. A method according to claim 4 wherein said step of increasing the resolution of said initial surface shading includes interpolating brightness values.

6. A method according to claim 4 wherein said step of filtering includes a process of Gaussian filtering.

7. A method according to claim 1, including the additional step of generating element vertex brightness values from said enhanced surface shading.

8. A method of shading surfaces generated from a radiosity simulation, in which surfaces have been divided into a plurality of elements, and a brightness value has been calculated for each of said elements, including the steps of

defining an initial surface shading in which the resolution of shading is determined in response to the highest element density of said surface;

processing element brightness values to generate brightness values for said initial surface shading;

filtering values of said initial surface shading to generate brightness values for an enhanced surface shading; and

in response to surface data storage requirements, selectively storing said enhanced surface shading, or vertex data derived from said enhanced surface shading.

9. A method according to claim 8, wherein said enhanced surface shading has a substantially higher resolution than said initial surface shading.

10. A method of rendering surface data in which a signals are supplied from a virtual set, including camera view signals and camera image signals, including steps of

rendering a first surface area from a radiosity texture;

rendering a second surface area from radiosity vertex values derived from an intermediate radiosity texture;

wherein

said radiosity textures have been generated by the steps of

defining an initial surface shading in which the resolution of shading is determined in response to the highest element density of said surface;

processing element brightness values to generate brightness values for said initial surface shading; and

filtering values of said initial surface shading to generate brightness values for an enhanced surface shading.

11. Apparatus for shading a surface generated from a radiosity simulation, including processing means and storage means including a storage area for instructions for said processing means, in which said surface has been divided into a plurality of elements, and a brightness value has been calculated for each of said elements, wherein said processing means is configurable to perform the steps of

defining an initial surface shading in which the resolution of shading is determined in response to the highest element density of said surface;

processing element brightness values to generate brightness values for said initial surface shading; and

filtering values of said initial surface shading to generate brightness values for an enhanced surface shading.

12. Apparatus according to claim 11, wherein the resolution of said initial surface shading is equal to the density of one texel per element vertex at the region of greatest element density within said surface generated from the radiosity simulation.

13. Apparatus according to claim 11, wherein said step of processing element brightness values includes combining the brightness of a plurality of elements to generate a single texel brightness value in said initial surface shading.

14. Apparatus according to claim 11 wherein said step of filtering includes the steps of

increasing the resolution of said initial surface shading; and

filtering said increased resolution shading.

15. Apparatus according to claim 14 wherein said step of increasing the resolution of said initial surface shading includes interpolating between brightness values.

16. Apparatus according to claim 14 wherein said step of filtering said increased resolution shading is performed by a process of Gaussian filtering.

17. Apparatus according to claim 11, including the additional step of

generating element vertex brightness values from said enhanced surface shading.

18. Apparatus for shading surfaces generated from a radiosity simulation, including processing means and storage means including a storage area for instructions for said processing means, in which a surface has been divided into a plurality of elements, and a brightness value has been calculated for each of said elements, wherein said processing means is configurable to perform the steps of

defining an initial surface shading in which the resolution of shading is determined in response to the highest element density of said surface;

processing element brightness values to generate brightness values for said initial surface shading;

filtering values of said initial surface shading to generate brightness values for an enhanced surface shading; and

in response to surface data storage requirements, selectively storing said enhanced surface shading, or vertex data derived from said enhanced surface shading.

19. Apparatus according to clam 18, wherein said enchanced surface shading has a substantially higher resolution than said initial surface shading.

20. Apparatus for rendering surface data generated from a radiosity simulation, in response to signals from a virtual set, including processing means and storage means including a storage area for instructions for said processing means, in which said surface has been divided into a plurality of elements, and a brightness value has been calculated for each of said elements, wherein said processing means is arranged to receive camera view signals and camera image signals from a virtual set, and is configurable to perform the steps of

rendering a first surface area from a radiosity texture;

rendering a second surface area from radiosity vertex values derived from an intermediate radiosity texture;

wherein

said radiosity textures have been generated by the steps of

defining an initial surface shading in which the resolution of shading is determined in response to the highest element density of said surface;

processing element brightness values to generate brightness values for said initial surface shading; and

filtering values of said initial surface shading to generate brightness values for an enhanced surface shading.

21. In a virtual set, in which real foreground images are combined with synthesised background images in real-time, means configured to generate said background image data, comprising

apparatus for shading a surface generated from a radiosity simulation, including processing means and storage means including a storage area for instructions for said processing means, in which said surface has been divided into a plurality of elements, and the brightness value has been calculated for each of said elements, wherein said processing means is configurable to perform the steps of

defining an initial surface shading in which the resolution of shading is determined in response to the highest element density of said surface;

processing element brightness values to generate brightness values for said initial surface shading; and

filtering values of said initial surface shading to generate brightness values for an enhanced surface shading.

22. Apparatus according to claim 21, wherein the resolution of said initial surface shading is equal to the density of one texel per element vertex at the region of greatest element density within said surface generated from the radiosity simulation.

23. Apparatus according to claim 21, wherein said step of processing element brightness values includes combining the brightness of a plurality of elements to generate a single texel brightness value in said initial surface shading.

24. Apparatus according to claim 21, wherein said step of filtering includes the steps of increasing the resolution of said initial surface shading;

and filtering said increased resolution.

25. Apparatus according to claim 24, wherein said step of filtering said increased resolution shading is performed by a process of Gaussian filtering.

26. A computer-readable medium having computer-readable instructions executable by a computer such that said computer performs the steps of:

shading a surface generated from a radiosity simulation, in which said surface has been divided into a plurality of elements, and a brightness value has been calculated for each of said elements, including the steps of

defining an initial surface shading in which the resolution of shading is determined in response to the highest element density of said surface;

processing element brightness values to generate brightness values for said initial surface shading; and

filtering values of said initial surface shading to generate brightness values for an enhanced surface shading.

27. A computer-readable medium according to claim 26, wherein said instructions are executed by said computer, such that the resolution of said initial surface shading is equal to the density of one texel per element vertex at the region of greatest element density within said surface generated from the radiosity simulation.

28. A computer-readable medium according to claim 26, wherein said instructions are executed by said computer such that said step of processing element brightness values includes combining the brightness of a plurality of elements to generate a single texel brightness value in said initial surface shading.

29. A computer-readable medium according to claim 26, wherein said instructions are executed by said computer such that said step of filtering includes the steps of increasing the resolution of said initial surface shading;

and filtering said increased resolution shading.

30. A computer-readable medium according to claim 29, wherein said instructions are executed by said computer such that said step of increasing the resolution of said initial surface shading includes interpolating brightness values.

31. A computer-readable medium according to claim 29, wherein said instructions are executed by said computer such that said step of filtering includes a process of Gaussian filtering.

32. A computer-readable medium according to claim 26, wherein said instructions are executed by said computer to perform the additional step of generating element vertex brightness values from said enhanced surface shading.