Patent ID: 8781234

Claim:
A method comprising: determining a first intermediate computation based only on even pixels in one coordinate of an image vector associated with a first image; storing the first intermediate computation to a first accumulation buffer; determining a second intermediate computation based only on odd pixels in the one coordinate of the image vector; storing the second intermediate computation to a second accumulation buffer; combining the first and second intermediate computations into a Hessian matrix computation, wherein the first and second intermediate computations are determined in parallel, and the Hessian matrix computation is determined for a plurality of interest points in parallel; and matching the first image to a second image based at least in part on the Hessian matrix computations, wherein determining each intermediate computation further includes: partitioning the image vector including pixels in the one coordinate into a plurality of partial image vectors, wherein each of the plurality of image vectors includes only even pixels or only odd pixels; calculating a box filter value for a first pixel in a partial image vector of the plurality of image vectors including only the even pixels or only the odd pixels; shifting the partial image vector by a fixed number of pixel positions, wherein the size of the partial image vector remains the same; calculating a box filter value for a second pixel in the partial vector; and summing the box filter value for the first pixel and the box filter value for the second pixel.