Real-time player for panoramic imaged-based virtual worlds

• US 6,028,584 A
• Filed: 08/29/1997
• Issued: 02/22/2000
• Est. Priority Date: 08/29/1997
• Status: Expired due to Term

• Current Assignee: Transpacific IP Group Limited
• Original Assignee: Industrial Technology Research Institute
• Inventors: Hsieh, Chun-Wei, Cheng, Tse, Chiang, Cheng-Chin
• Primary Examiner(s): Hjerpe, Richard A.
• Assistant Examiner(s): Laneau, Ronald
• Application Number:
  US08/920,760
• Time in Patent Office: 907 Days
• Field of Search: 345/118, 345/121, 345/425, 345/419, 345/430, 345/431, 395/125, 395/127
• US Class Current: 345/628
• CPC Class Codes: G06T 15/10 Geometric effects
• CPC Class Codes: G06T 3/12 Panospheric to cylindrical image transformations

Abstract

A method and apparatus for displaying a selected portion of a panoramic image onto a view plane is provided. The method provides an environment map in the form of a plurality of pixel values representative of the panoramic image. A first portion of the pixel values representative of a selected first area of the panoramic image is mapped to a projection buffer. A second portion of the first portion of pixel values, representative of a desired area of the panoramic image to be viewed is mapped to the view plane. The view plane is displayed on the display.

Claims

1. A method of displaying a selected portion of a panoramic image onto a display, the method comprising:

providing an environment map in the form of a plurality of pixel values representative of the panoramic image, wherein the environment map represents the panoramic image wrapped onto a hypothetical cylinders;

mapping, to a projection buffer, a first portion of the pixel values representative of a selected first area of the panoramic image, wherein the first area of the panoramic image mapped onto the projection buffer represents a horizontal view of the image from a viewing position lying along a longitudinal axis of the cylinder and at a midpoint of the height of the cylinder, the projection buffer lying along a tangent of the cylinder and between the viewing position and the view plane;

mapping, to a view plane, a second portion of the first portion of pixel values, representative of a desired area of the panoramic image to be viewed; and

displaying the view plane on the display.

2. The method of claim 1 wherein the plurality of pixel values representative of the panoramic image are ordered in a first plurality of scanlines, the first portion of the pixel values representative of the selected first area of the panoramic image are ordered in a second plurality of scanlines, and the second portion of the first portion of pixel values are ordered in a third plurality of scanlines.

3. The method of claim 2 wherein the second plurality of scanlines form a first rectangular area and the third plurality of scanlines form a second rectangular area smaller than the first rectangular area.

4. The method of claim 3 wherein the step of mapping a first portion of the pixel values representative of a selected first area of the panoramic image includes generating a lookup table having entries corresponding to starting and ending points of each of the second plurality of scanlines.

5. The method of claim 4 wherein the step of mapping a second portion of the first portion of pixel values includes calculating starting and ending points of each of the third plurality of scanlines.

6. The method of claim 3 wherein the step of mapping a first portion of the pixel values representative of a selected first area of the panoramic image includes generating a lookup table having entries corresponding to grouped sets of neighboring ones of the second plurality of scanlines.

7. The method of claim 6 wherein the second plurality of scanlines of each grouped set have the same starting and ending positions.

8. The method of claim 6 wherein the number of neighboring ones of the second plurality of scanlines in each grouped set is dynamically changed.

9. A system for displaying a selected portion of a panoramic image onto a view plane, the system comprising:

a video memory which stores a plurality of pixel values representative of the panoramic image wrapped onto a cylinder, the video memory having a first bit-mapped area representing a projection buffer and a second bit-mapped area representing the view plane, wherein the first area of the panoramic image mapped onto the projection buffer represents a horizontal view of the image from a viewing position lying along a longitudinal axis of the cylinder at a midpoint of the height of the cylinder, the projection buffer lying along a tangent of the cylinder and between the viewing position and the view plane;

an input device which identifies a first portion of the panoramic image desired to be viewed;

a microprocessor which maps, to the first bit-mapped area, a portion of the pixel values representative of a selected first area of the panoramic image;

a video processor which maps, to the second bit-mapped area and in response to commands from the microprocessor, a second portion of the first portion of pixel values, representative of a desired area of the panoramic image to be viewed; and

a video display which displays a second portion of the panoramic image.

10. The system of claim 9 wherein the plurality of pixel values representative of the panoramic image are ordered in a first plurality of scanlines, the first portion of the pixel values representative of the selected first area of the panoramic image are ordered in a second plurality of scanlines, and the second portion of the first portion of pixel values are ordered in a third plurality of scanlines.

11. The system of claim 10 wherein the microprocessor maps the plurality of pixel values to generate a lookup table representative of a first portion of the panoramic image.

12. The system of claim 11 wherein the video processor includes hardware blitter.