Optimizing continuity in multiscale imagery

Abstract

Multiscale imagery often combines several sources with differing appearance. For instance, Internet-based maps contain satellite and aerial photography. Zooming within these maps may reveal jarring transitions. We present a scheme that creates a visually smooth mipmap pyramid from stitched imagery at several scales. The scheme involves two new techniques. The first, structure transfer , is a nonlinear operator that combines the detail of one image with the local appearance of another. We use this operator to inject detail from the fine image into the coarse one while retaining color consistency. The improved structural similarity greatly reduces inter-level ghosting artifacts. The second, clipped Laplacian blending , is an efficient construction to minimize blur when creating intermediate levels. It considers the sum of all inter-level image differences within the pyramid. We demonstrate continuous zooming of map imagery from space to ground level.