1. A method, comprising: executing an image analysis module on one or more processors of a computing device to perform: characterizing each image in a set of images with a set of sparse feature descriptors and a set of dense feature descriptors, both the set of sparse feature descriptors and the set of dense feature descriptors being calculated based on a fixed rotation; indexing the set of images in a feature index that includes the set of sparse feature descriptors for each image of the set of images, and the set of dense feature descriptors for each image of the set of images, the set of sparse feature descriptors indexed independently from the set of dense feature descriptors; characterizing a query image with the set of sparse feature descriptors of the query image, and with the set of dense feature descriptors of the query image; performing a rotated local Bag-of-Features (BoF) operation upon a set of rotated query images and the set of images; and ranking each of the set of images based on the rotated local Bag-of-Features (BoF) operation.