CaMor: Screw Interpolation between Perspective Projections of Partial Views of Rectangular Images

Abstract

CaMor is a tool for generating an animation from a single drawing or photograph that represents a partial view of a perspective projection of a planar shape or image that contains portions of only 3 edges of an unknown rectangle. The user identifies these portions and indicates where the corresponding lines should be at the end of the animation. CaMor produces a non-affine animation of the entire plane by combining (1) a new rectification procedure that identifies the orientation in 3D of a rectangle from the partial image of its perspective projection, (2) a depth adjustment that ensures that the two rectified rectangles are congruent in 3D, (3) a screw motion that interpolates in 3D between the two congruent shapes, and (4) at each frame, a perspective projection of a user-selected portion of the original image. The animation may be modified interactively by adjusting the final positions of the lines or the focal length. We suggest applications to the animation of hand-drawn scenes, to the morph between two photographs, and to the intuitive design of camera motions for indoor and street scenes.