Fast Approximate Nearest-Neighbor Field by Cascaded Spherical Hashing

I. Torres-Xirau, J. Salvador, E. PĂ©rez-Pellitero. ACCV 2014

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Spherical Hashing Unsupervised ACCV

We present an efficient and fast algorithm for computing approximate nearest neighbor fields between two images. Our method builds on the concept of Coherency-Sensitive Hashing (CSH), but uses a recent hashing scheme, Spherical Hashing (SpH), which is known to be better adapted to the nearest-neighbor problem for natural images. Cascaded Spherical Hashing concatenates different configurations of SpH to build larger Hash Tables with less elements in each bin to achieve higher selectivity. Our method amply outperforms existing techniques like PatchMatch and CSH, and the experimental results show that our algorithm is faster and more accurate than existing methods.