1. A method for rectifying an input digital image including warped textual information, the method implemented at least in part by a data processing system and comprising: receiving the input digital image; analyzing the input digital image to determine local orientations for a plurality of local image regions; determining an orientation vector field responsive to the determined local orientations; determining a set of streamlines responsive to the orientation vector field; forming a global deformation function by interpolating between the streamlines; forming a rectified image by rectifying the input digital image responsive to the global deformation function; and storing the rectified image in a processor-accessible memory.