Patent ID: 6118595
Filing Date: 2000-09-12
Classification: G03B

Abstract:
A process for constructing an image of substantially all four-pi radians of a view, the view having a zenith direction around which an azimuth is measured starting at a view-prime-meridian, and from which a polar angle is measured, the process comprising the steps of:i) fixing a camera at a location appropriate for photographing the view;ii) determining a set of directions in which to aim the camera so as to capture substantially all four-pi radians of the view, each direction in the set of directions indicated by an azimuth and a polar angle, each direction having a field of view, the set of directions based on the field of view in each direction and a requirement that a photograph taken in any one of the directions have a partial overlap with photographs taken in at least four other of the directions, the set of directions including the zenith and the nadir;iii) taking a photograph in each of the directions in the set of directions;iv) providing a view projection by arranging in a two-dimensional layout portions of the photographs so as to provide without repetition substantially all four-pi radians of the view, the portions of the photographs so arranged constituting the view projection; andv) bending the view projection so as to create a surface that conforms to a surface of a closed-surface object;wherein the step of providing a view projection comprises the steps of:a) arranging the photographs, except for the photographs in the zenith and nadir directions, in an array for masking, the array for masking having rows and columns of photographs including a first row and a last row, the first row having photographs taken in the nearly zenith direction and the last row having photographs taken in the nearly nadir direction, the array for masking showing all overlap in photographs in adjacent columns but overlaid to conceal all overlap between photographs in adjacent rows;b) augmenting the array for masking by duplicating the photograph in the zenith direction and re-positioning and re-orienting it so as to have a duplicate of the photograph in the zenith direction adjacent each photograph in the first row and oriented so as to continue in a polar sense the image conveyed by the photograph in the first row, and doing likewise for the photograph in the vertical direction and each photograph in the last row;c) masking the array for masking with a mask appropriate for selecting enough of portions of the photographs to substantially show the four-pi view without showing overlap, the mask having final regions that in combination provide the four-pi view without overlap, and deforming the mask, or the array for masking, or both so that the mask and array for masking correspond substantially in both height and width; andd) eliminating the portions of the array for masking not within the final regions, leaving behind the view projection.