Cylindrical to planar image mapping using scanline coherence
First Claim
1. In a computer controlled display system, a method for displaying perspective corrected portions of an environment map comprising the steps of:
- a) providing a cylindrical environment map, said cylindrical environment map comprised of a plurality of pixel shading values ordered in a first plurality of scanlines;
b) identifying a first portion of said cylindrical environment map;
c) mapping said first portion to a viewing plane having a second plurality of pixel shading values ordered in a second plurality of scanlines, said mapping including determining a plurality of scaling factors and applying the scaling factor corresponding to a scanline of said first plurality of scanlines to each pixel shading value in said scanline to obtain said second plurality of pixel shading values, said viewing plane having pre-determined dimensions; and
d) displaying said viewing plane.
2 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus for generating perspective views of a scene. With a viewing position at the center of to be cylindrical environment map, different views can be obtained by rotating the viewing direction either horizontally or vertically. The horizontal construction method of the present invention generally involves the steps of: determining the portion of the cylindrical map to be viewed; vertically interpolating pixel values in the portion of the cylindrical map to be viewed and mapping to a viewing plane; and displaying the viewing plane. The vertical construction method of the present invention generally involves the steps of: determining the portion of the cylindrical map to be viewed; vertically interpolating pixel values in the portion of the cylindrical map robe viewed and mapping to a vertical plane; horizontally interpolating pixel values in the vertical plane and mapping to the viewing plane; and displaying the viewing plane.
-
Citations
17 Claims
-
1. In a computer controlled display system, a method for displaying perspective corrected portions of an environment map comprising the steps of:
-
a) providing a cylindrical environment map, said cylindrical environment map comprised of a plurality of pixel shading values ordered in a first plurality of scanlines; b) identifying a first portion of said cylindrical environment map; c) mapping said first portion to a viewing plane having a second plurality of pixel shading values ordered in a second plurality of scanlines, said mapping including determining a plurality of scaling factors and applying the scaling factor corresponding to a scanline of said first plurality of scanlines to each pixel shading value in said scanline to obtain said second plurality of pixel shading values, said viewing plane having pre-determined dimensions; and d) displaying said viewing plane. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. In a computer controlled display system, a method for displaying perspective views of a cylindrical environment map, said cylindrical environment map comprised of a plurality of pixel shading values, said method comprising the steps of:
-
a) determining a viewpoint from which to view said cylindrical environment map; b) identifying a rotation direction; c) if said rotation direction is horizontal, performing the steps of; identifying a first portion of said cylindrical environment map to be viewed, said first portion having a plurality of vertical scanlines; identifying a first viewing plane; scaling said first portion vertically to said viewing plane by generating a first plurality of scaling factors and applying the scaling factor corresponding to each of said plurality of vertical scanlines to each of said plurality of vertical scanlines; mapping said first viewing plane to a coordinate system associated with a viewing device on which said perspective view will be displayed; d) if said rotation direction is vertical, performing the steps of; identifying a second portion of said cylindrical environment map to be viewed, said second portion having a plurality of scanlines; identifying a vertical plane corresponding to said second portion and said vertical rotation; scaling said second portion vertically to said vertical plane by generating a second plurality of scaling factors and applying the scaling factor corresponding to each of said plurality of scanlines to each of said plurality of scanlines; identifying a second viewing plane; scaling said vertical plane horizontally to said second viewing plane; mapping said second viewing plane to a coordinate system associated with a viewing device on which said perspective view will be displayed. - View Dependent Claims (8, 9, 10, 11, 12, 13)
-
-
14. A computer controlled display system for generating perspective views of a cylindrical environment map, said system comprising:
-
a) first storage means for storing said cylindrical environment map; b) second storage means for storing pixel shading values; c) a display means for displaying a perspective view, said display means coupled to said second storage means; d) means for identifying a portion of said cylindrical environment map to be displayed; e) horizontal scaling means coupled to said means for identifying a portion of said cylindrical environment map to be displayed and said second storage means, said horizontal scaling means for generating pixel shading values on a horizontal scanline by determining a plurality of horizontal scaling factors and applying the scaling factor corresponding to a horizontal scanline of said plurality of horizontal scanlines to each pixel shading value in said horizontal scanline; and f) vertical scaling means coupled to said means for identifying a portion of said cylindrical environment map to be displayed and said second storage means, said vertical scaling means for generating pixel shading values on a vertical scanline by determining a plurality of vertical scaling factors and applying the scaling factor corresponding to a vertical scanline of said plurality of vertical scanlines to each pixel shading value in said vertical scanline. - View Dependent Claims (15, 16, 17)
-
Specification