EFFICIENT RENDERING OF PANORAMIC IMAGES, AND APPLICATIONS THEREOF

• US 20080291201A1
• Filed: 05/25/2007
• Published: 11/27/2008
• Est. Priority Date: 05/25/2007
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: LAFON, Stephane
• Granted Patent: US 7,843,451 B2
• Time in Patent Office: Days
• US Class Current: 345/427
• CPC Class Codes: G06T 15/205 Image-based rendering

Abstract

A fast renderer for panoramic images is herein disclosed. In an embodiment, a precomputation is made of (a) a region on a surface defined by a first transformation from a viewport to the surface and (b) a second transformation that maps from the precomputed region to the viewport. In order to render the surface on the viewport, the renderer determines what portion of the image intersects with the precomputed region and proceeds to apply the precomputed second transformation to the portion of the image, thereby resulting in a transformed image which can be rendered in the viewport for display.

Claims

1. A method for rendering a surface, comprising:

(a) computing a region on the surface defined by a first transformation from a viewport to the surface; and

(b) computing a second transformation that maps from the region to the viewport;

(c) determining a portion of an image which intersects with the region;

(d) applying the second transformation to the portion of the image which intersects with the region, to obtain a transformed image; and

(e) rendering the transformed image in the viewport for display.

2. The method of claim 1, wherein the computing (a) comprises computing a region on a cylinder.

3. The method of claim 1, wherein the computing (a) comprises computing the region on a first mesh defined by the first transformation from a second mesh to the first mesh, and

wherein the computing (b) comprises computing the second transformation that maps from the first mesh to the second mesh.

4. The method of claim 1, wherein the computing (a) comprises computing the first transformation as a continuous transformation from a voxel to a pixel, and

wherein the computing (b) comprises computing the second transformation as a continuous transformation from a voxel to a pixel.

5. The method of claim 1, further comprising:

(f) translating the image;

(g) determining a second portion of the image translated in (f) that intersects with the region computed in (a); and

(h) applying the second transformation computed in (b) to the second portion of the image determined in (g), resulting in a second transformed image, which is rendered in the viewport for display.

6. The method of claim 5, further comprising determining an interpolation between the transformed image determined in (d) and the second transformed image determined in (h).

7. The method of claim 1, further comprising adjusting the image based on an angle of a camera that captured the image.

8. The method of claim 1, wherein the determining (c) comprises determining a portion of a panoramic image which intersects with the region.

9. A system for rendering a surface, comprising:

a server that computes a region on the surface defined by a first transformation from a viewport to the surface and computes a second transformation that maps from the region to the viewport; and

a panorama viewer that determines a portion of an image which intersects with the region on the surface and applies the second transformation to the portion of the image intersecting with the region on the surface, resulting in a first transformed image, which is rendered in the viewport for display.

10. The system of claim 9, wherein the surface is a cylinder.

11. The system of claim 9, wherein a mesh is defined on the viewport and a mesh is defined on the surface, and wherein the first and second transformations are from one mesh to the other.

12. The system of claim 9, wherein first and second transformations are continuous transformations from a voxel to a pixel.

13. The system of claim 9, wherein the panorama viewer, in response to a user input, translates the image, determines a second portion of the translated image that intersects with the computed region, and applies the second transformation to the second portion of the image determined, resulting in a second transformed image, which is rendered in the viewport for display.

14. The system of claim 9, wherein the panorama viewer determines an interpolation between the first and second transformed images.

15. The system of claim 9, wherein the image is adjusted based on an angle of a camera that captured the image.

16. The system of claim 9, wherein the image is a panoramic image.