TECHNIQUES FOR PROCESSING IMAGE DATA GENERATED FROM THREE-DIMENSIONAL GRAPHIC MODELS

• US 20130063418A1
• Filed: 09/12/2011
• Published: 03/14/2013
• Est. Priority Date: 09/12/2011
• Status: Active Grant

• Current Assignee: Disney Enterprises Incorporated (The Walt Disney Company)
• Original Assignee: Disney Enterprises Incorporated (The Walt Disney Company)
• Inventors: KASCHALK, MICHAEL, DANIELS, ERIC A., WHITED, BRIAN S., ODERMATT, KYLE D., OSBORNE, PATRICK T.
• Granted Patent: US 9,041,717 B2
• Time in Patent Office: Days
• US Class Current: 345/419
• CPC Class Codes: G06T 13/20 3D [Three Dimensional] animation
• CPC Class Codes: G06T 15/005 General purpose rendering architectures
• CPC Class Codes: G06T 2213/00 Indexing scheme for animation

Abstract

Techniques are disclosed for creating animated video frames which include both computer generated elements and hand drawn elements. For example, a software tool may allows an artist to draw line work (or supply other 2D image data) to composite with an animation frame rendered from a three dimensional (3D) graphical model of an object. The software tool may be configured to determine how to animate such 2D image data provided for one frame in order to appear in subsequent (or prior) frames in a manner consistent with changes in rendering the underlying 3D geometry.

Claims

1. A computer-implemented method for processing an animation frame, the method comprising:

identifying a first animation frame rendered by one or more processors, wherein the first animation frame renders three-dimensional (3D) geometry corresponding to a 3D model object at a first point in time; and

generating a screen space velocity map indicating a dynamic velocity of one or more coordinates in the first animation frame relative to changes in points on the 3D model object occurring over one or more specified time steps.

2. The method of claim 1, wherein the one or more coordinates in the screen space velocity map are mapped to pixel coordinates in the first animation frame, and wherein the dynamic velocity of each coordinate includes both a magnitude and direction of pixel movement.

3. The method of claim 2, further comprising:

generating a visual representation of the screen space velocity map, wherein the visual representation encodes a magnitude and direction of pixel movement using a specified color scheme.

4. The method of claim 1, further comprising:

receiving two-dimensional (2D) image data to composite with the first animation frame; and

animating the 2D image data over the specified time step according to the dynamic velocity of the one or more coordinates in the screen space velocity map.

5. The method of claim 1, wherein the one or more time steps move forward through a rendered animation of the 3D geometry.

6. The method of claim 1, wherein the one or more time steps move backward through a rendered animation of the 3D geometry.

7. A computer-readable storage medium storing a program, which, when executed by a processor performs an operation for processing an animation frame, the operation comprising:

identifying a first animation frame rendered by one or more processors, wherein the first animation frame renders three-dimensional (3D) geometry corresponding to a 3D model object at a first point in time; and

generating a screen space velocity map indicating a dynamic velocity of one or more coordinates in the first animation frame relative to changes in points on the 3D model object occurring over one or more specified time steps.

8. The computer-readable storage medium of claim 7, wherein the one or more coordinates in the screen space velocity map are mapped to pixel coordinates in the first animation frame, and wherein the dynamic velocity of each coordinate includes both a magnitude and direction of pixel movement.

9. The computer-readable storage medium of claim 8, wherein the operation further comprises:

generating a visual representation of the screen space velocity map, wherein the visual representation encodes a magnitude and direction of pixel movement using a specified color scheme.

10. The computer-readable storage medium of claim 7, wherein the operation further comprises:

receiving two-dimensional (2D) image data to composite with the first animation frame; and

animating the 2D image data over the specified time step according to the dynamic velocity of the one or more coordinates in the screen space velocity map.

11. The computer-readable storage medium of claim 7, wherein the one or more time steps move forward through a rendered animation of the 3D geometry.

12. The computer-readable storage medium of claim 7, wherein the one or more time steps move backward through a rendered animation of the 3D geometry.

13. A system, comprising:

a processor; and

a memory, wherein the memory includes an application program configured to perform an operation for evaluating pixels in an animation frame, the operation comprising;

identifying a first animation frame rendered by one or more processors, wherein the first animation frame renders three-dimensional (3D) geometry corresponding to a 3D model object at a first point in time, and

generating a screen space velocity map indicating a dynamic velocity of one or more coordinates in the first animation frame relative to changes in points on the 3D model object occurring over one or more specified time steps.

14. The system of claim 13, wherein the one or more coordinates in the screen space velocity map are mapped to pixel coordinates in the first animation frame, and wherein the dynamic velocity of each coordinate includes both a magnitude and direction of pixel movement.

15. The system of claim 14, wherein the operation further comprises:

generating a visual representation of the screen space velocity map, wherein the visual representation encodes a magnitude and direction of pixel movement using a specified color scheme.

16. The system of claim 13, wherein the operation further comprises:

receiving two-dimensional (2D) image data to composite with the first animation frame; and

animating the 2D image data over the specified time step according to the dynamic velocity of the one or more coordinates in the screen space velocity map.

17. The system of claim 13, wherein the one or more time steps move forward through a rendered animation of the 3D geometry.

18. The system of claim 13, wherein the one or more time steps move backward through a rendered animation of the 3D geometry.

19. A computer-implemented method for generating a two-dimensional (2D) silhouette for geometry of a 3D graphical model, the method comprising:

defining a continuous surface parameterization for at least a portion of the geometry representing the 3D graphical model, wherein a first dimension of the 2D surface parameterization intersects a portion of a surface of the 3D graphical model;

tracking a silhouette feature over one or more frames, wherein the tracking includes;

identifying a plurality of points on the first dimension of the surface parameterization,

for each of identified point, determining at least one second dimension of the surface parameterization, each providing a tangent point on the surface of the 3D model tangent to a viewpoint of a rendering camera, and

connecting the tangent points to produce geometry defining a 2D silhouette for the portion of the surface of the 3D graphical model in each of the one or more frames.

20. The method of claim 19, wherein the first dimension of the 2D surface parameterization is determined as a cylindrical feature wrapping a portion of the surface of the 3D graphical model.

21. The method of claim 20, further comprising, deriving a plurality of closed loops generally perpendicular to an axis of the cylindrical feature, and wherein determining at least one second dimension of the surface parameterization comprises identifying at least one point on the closed loop tangent to the viewpoint of the rendering camera.

22. The method of claim 19, further comprising, extruding the tangent points in a direction perpendicular to both the surface of the 3D graphical model and a line-of-sight of the rendering camera to generate a 2D ribbon silhouette tracing an edge of the 3D graphical model in each of the one or more frames.

23. The method of claim 22, further comprising:

applying a graphical effect to the 2D ribbon silhouette tracing the edge of the 3D graphical model;

generating screen space velocity maps indicating a dynamic velocity of one or more coordinates in the 2D ribbon silhouette relative to changes in points on the 3D model object occurring over each of the one or more frames; and

animating the 2D ribbon silhouette over each of the one or more frames according to the dynamic velocity of the one or more coordinates in the screen space velocity maps.

24. The method of claim 22, further comprising, compositing the animated 2D ribbon silhouette with the one or more frames.

25. A computer-readable storage medium storing a program, which, when executed by a processor performs an operation for generating a two-dimensional (2D) silhouette for geometry of a 3D graphical model, the operation comprising:

defining a continuous surface parameterization for at least a portion of the geometry representing the 3D graphical model, wherein a first dimension of the 2D surface parameterization intersects a portion of a surface of the 3D graphical model;

tracking a silhouette feature over one or more frames, wherein the tracking includes;

identifying a plurality of points on the first dimension of the surface parameterization,

for each of identified point, determining at least one second dimension of the surface parameterization, each providing a tangent point on the surface of the 3D model tangent to a viewpoint of a rendering camera, and

connecting the tangent points to produce geometry defining a 2D silhouette for the portion of the surface of the 3D graphical model in each of the one or more frames.

26. The computer-readable storage medium of claim 25, wherein the first dimension of the 2D surface parameterization is determined as a cylindrical feature wrapping a portion of the surface of the 3D graphical model.

27. The computer-readable storage medium of claim 26, wherein the operation further comprises, deriving a plurality of closed loops generally perpendicular to an axis of the cylindrical feature, and wherein determining at least one second dimension of the surface parameterization comprises identifying at least one point on the closed loop tangent to the viewpoint of the rendering camera.

28. The computer-readable storage medium of claim 25, wherein the operation further comprises, extruding the tangent points in a direction perpendicular to both the surface of the 3D graphical model and a line-of-sight of the rendering camera to generate a 2D ribbon silhouette tracing an edge of the 3D graphical model in each of the one or more frames.

29. The computer-readable storage medium of claim 28, wherein the operation further comprises:

applying a graphical effect to the 2D ribbon silhouette tracing the edge of the 3D graphical model;

generating screen space velocity maps indicating a dynamic velocity of one or more coordinates in the 2D ribbon silhouette relative to changes in points on the 3D model object occurring over each of the one or more frames; and

animating the 2D ribbon silhouette over each of the one or more frames according to the dynamic velocity of the one or more coordinates in the screen space velocity maps.

30. The computer-readable storage medium of claim 28, wherein the operation further comprises, compositing the animated 2D ribbon silhouette with the one or more frames.