Inverse kinematics for motion-capture characters

• US 8,334,872 B2
• Filed: 06/30/2009
• Issued: 12/18/2012
• Est. Priority Date: 05/29/2009
• Status: Active Grant

• Current Assignee: Two PIC MC LLC (The Walt Disney Company)
• Original Assignee: Two PIC MC LLC (The Walt Disney Company)
• Inventors: Epps, Doug, Reid, Nate
• Primary Examiner(s): Nguyen, Phu K
• Application Number:
  US12/495,488
• Publication Number:
  US 20100302258A1
• Time in Patent Office: 1,267 Days
• Field of Search: 345/420, 345/473, 345/474, 345/475, 345/582
• US Class Current: 345/474
• CPC Class Codes: G06T 13/40 of characters, e.g. humans, animals or virtual beings

Abstract

A method for a computer system comprising receiving a displacement for a first object model surface from a user determined in response to a first physical motion captured pose, determining a weighted combination of a first displacement group and a second displacement group from the displacement, wherein the first displacement group is determined from displacements between the first object model surface and a second object model surface, wherein the second object model surface is determined from displacements between a second physical motion captured pose, wherein the second displacement group is determined from displacements between the first object model surface and a third object model surface, wherein the third object model surface is determined from a third physical motion captured pose, determining a fourth object model surface from the first object model surface and the weighted combination, and displaying the fourth object model surface to the user on a display.

Claims

1. A method for a computer system comprising:

receiving a surface displacement for a location on a first surface of a model of an object from a user via a user input device of the computer system, wherein the first surface of the model of the object is determined in response to a first motion captured pose of the object;

determining a weighted combination of a first surface displacement group and a second surface displacement group in response to the surface displacement in the computer system, wherein the first surface displacement group is determined in response to displacements between the first surface of the model of the object and a second surface of the model of the object, wherein the second surface of the model of the object is determined in response to a second motion captured pose of the object, wherein the second surface displacement group is determined in response to displacements between the first surface of the model of the object and a third surface of the model of the object, wherein the third surface of the model of the object is determined in response to a third motion captured pose of the object;

determining a fourth surface of the model of the object in the computer system in response to the first surface of the model of the object and the weighted combination of the first surface displacement group and the second surface displacement group; and

displaying the fourth surface of the model of the object to the user on a display of the computer system.

2. The method of claim 1 wherein determining the weighted combination comprises using a cost function selected from a group consisting of:

a least squares and an energy function.

3. The method of claim 1 further comprising:

posing the object in the first motion captured pose, wherein the object includes a plurality of physical markers;

capturing a plurality of images of the object in the first motion captured pose, wherein the plurality of images includes locations of physical markers from the plurality of physical markers; and

determining the second surface of the model of the object in response to the plurality of images.

4. The method of claim 1 further comprising:

determining the location on the first surface of the model of the object from the user via a user input device, wherein the location is associated with a surface descriptor;

determining another location from the user via the user input device; and

determining the surface displacement and a direction in response to the location and the other location.

5. The method of claim 1

wherein the surface descriptor comprises a wire-frame model comprising a plurality of vertices;

and

wherein the surface displacement comprises a displacement of at least one vertex from the plurality of vertices.

6. The method of claim 1 further comprising:

rendering an image in response to the fourth surface of the model of the object;

storing a representation of the image in a tangible memory; and

displaying the image retrieved from the tangible memory to a user on a display;

wherein the tangible memory is selected from a group consisting of;

an optical storage medium, a magnetic storage medium, an electrical storage medium, film medium.

7. A tangible media having stored thereon a executable program code for causing a processor to implement the method comprising:

receiving a surface displacement for a location on a first surface of a model of an object from a user, wherein the first surface of the model of the object is determined in response to a first motion captured pose of the object;

determining a weighted combination of a first surface displacement group and a second surface displacement group in response to the surface displacement, wherein the first surface displacement group is determined in response to displacements between the first surface of the model of the object and a second surface of the model of the object, wherein the second surface of the model of the object is determined in response to a second motion captured pose of the object, wherein the second surface displacement group is determined in response to displacements between the first surface of the model of the object and a third surface of the model of the object, wherein the third surface of the model of the object is determined in response to a third motion captured pose of the object; and

determining a fourth surface of the model of the object in response to the first surface of the model of the object and the weighted combination of the first surface displacement group and the second surface displacement group.

8. The tangible media of claim 7 wherein the method further comprises:

determining the location on the first surface of the model of the object from the user, wherein the location is associated with a surface descriptor;

determining another location from the user; and

determining the surface displacement and a direction in response to the location and the other location.

9. The tangible media of claim 7 wherein the surface descriptor comprises a wire-frame model comprising a plurality of vertices and wherein the surface displacement comprises a displacement of at least one vertex from the plurality of vertices.

10. The tangible media of claim 7 wherein the method further comprises rendering an image in response to the fourth surface of the model of the object.

11. The tangible media of claim 10 where the method further comprises storing a representation of the image in another tangible medium, wherein the other tangible medium is selected from a group consisting of:

an optical storage medium, a magnetic storage medium, an electrical storage medium and a film medium.

12. A computer system comprising a processor coupled to a memory storage device, wherein the memory storage device has stored thereon an executable program code to cause the processor to implement a method comprising:

receiving a surface displacement for a location on a first surface of a model of an object from a user via a user input device of the computer system, wherein the first surface of the model of the object is determined in response to a first motion captured pose of the object;

using the processor to determine a weighted combination of a first surface displacement group and a second surface displacement group in response to the surface displacement in the computer system, wherein the first surface displacement group is determined in response to displacements between the first surface of the model of the object and a second surface of the model of the object, wherein the second surface of the model of the object is determined in response to a second motion captured pose of the object, wherein the second surface displacement group is determined in response to displacements between the first surface of the model of the object and a third surface of the model of the object, wherein the third surface of the model of the object is determined in response to a third motion captured pose of the object;

determining a fourth surface of the model of the object in the computer system in response to the first surface of the model of the object and the weighted combination of the first surface displacement group and the second surface displacement group; and

displaying the fourth surface of the model of the object to the user on a display of the computer system.

13. The computer system of claim 12 wherein the method further comprises:

determining the location on the first surface of the model of the object from the user via a user input device of the computer system, wherein the location is associated with a surface descriptor;

determining another location from the user via the user input device; and

determining the surface displacement and a direction in response to the location and the other location.

14. The computer system of claim 12 wherein the surface descriptor comprises a wire-frame model comprising a plurality of vertices and wherein the surface displacement comprises a displacement of at least one vertex from the plurality of vertices.

15. The computer system of claim 12 wherein the method further comprises:

rendering an image in response to the fourth surface of the model of the object; and

displaying the image to a user on a display.

16. The computer system of claim 15 where the method further comprises storing a representation of the image in a tangible memory, wherein the tangible memory is selected from a group consisting of:

an optical storage medium, a magnetic storage medium, an electrical storage medium and a film medium.