Principle of Four-Circle Format (4CF) imaging of 3-D objects
- A novel method of representing the surface data of objects is described here.
(patent applied - 201741026182)
- The shape and colour detail of a 3-D object could be captured among four circular zones, as illustrated below.
- The two grey colored circles in the upper region contains the coded data of cube shape.
- The two color circles in the lower region stores the surface color detail of Rubik's cube.
- The left and right circles of the image pertain to the front and back portions of the object.
- A geometrical method of mapping the object's surface to the circular zone is outlined below:
Demonstration of Image Retrieval
- A suitable center point O within the 3-D object model is first chosen.
- An imaginary sphere centered at O and radius (say, 125 units) is superposed on the model.
- Let F and B denote front and back direction pole points on the sphere surface.
- By stereographic projection from B/F poles, the front/back hemispheres can be mapped as circles.
- As depicted in the figure, ray from O to a surface point P intersects the sphere surface at r .
- Extension of line segment B-r intersects the tangential plane of F at p .
- The distance OP (after scaling) is coded as a grey scale pixel value at p, to trace the shape.
- While the (Red,Green,Blue) color value of P is assigned to the p point in the bottom circle.
- The obtained (1000x1000 pixel) raster image contains the full solid angle view of the object.
- A decoder program can interpret the 4CF image to render interactive views on user screen.