1. A method for obtaining structural information from a digital image by an electronic device, comprising: obtaining a digital image; determining a region of interest from the digital image, wherein the region of interest comprises a contiguous subset of the digital image; determining a corresponding gradient vector for each pixel in the region of interest; transforming each pixel in the region of interest in accordance with a transform, comprising: determining, for each pixel in the region of interest, a first set of pixels, wherein the first set of pixels includes all pixels along a line that is collinear with the corresponding gradient vector, wherein the line extends to two edges of the region of interest, and incrementing, for each pixel in the region of interest, all values in a transform space corresponding to pixels in the first set of pixels that are in the same direction as the corresponding gradient vector; and detecting at least one curved item in the digital image based on the transform space.