Two related methods for the hierarchical representation of curve information are presented. First, edge pyramids are defined and discussed. An edge pyramid is a sequence of successively lower resolution images, each image containing a summary of the edge or curve information in its predecessor. This summary includes the average magnitude and direction in a neighborhood of the preceding image, as well as an intercept in that neighborhood and a measure of the error in the direction estimate. An edge quadtree is a variable-resolution representation of the linear information in the image. It is constructed by recursively splitting the image into quadrants based on magnitude, direction and intercept information. Advantages of the edge quadtree representation are its ability to represent several linear features in a single tree, its registration with the original image, and its ability to perform many common operations efficiently.