Abstract:

Example-based methods are effective for parameter estimation problems when the underlying system is simple or the dimensionality of the input is low. For complex and high-dimensional problems wuch as pose estimation, the number of required examples and the computational complexity rapidly become prohibitively high. We introduce a new algorithm that leans a set of hashing functions that efficiently index examples in a way relevant to a particular estimation task. Our algorithm extends locality-sensitive hashing, a recently developed method to find approximate neighbors in time sublinear in the number of examples. This method depends critically on the choice of has functions: we show how to find the set of hash funcations that are optimally relevant to a particular estimation problem. Experiments demonstrate that the resulting algorithm, which we call Parameter-Sensitive Hashing, can rapidly and accurately estimate the articulated pose of human figures from a large database of example images.