Matching Canny edgels to compute the principal components of optic flow

摘要

A relaxation algorithm for the computation of optic flow at edge elements (edgels) is presented. Flow is estimated only at intensity edges of the image. Edgels, extracted from an intensity image, are used as the basis for the algorithm. A matching strength or weight surface is computed around each edgel and neighbourhood support is obtained to enhance the matching strength. A principal moments method is used to determine the flow from this weight surface. The output of the algorithm is, for each edgel a pair of orthogonal components of the estimate of the flow. Associated with each component is a confidence measure. Examples of the output of the algorithm are given, and tests of its accuracy are discussed.