Invariance Properties of AM-FM Image Features with Application to Template Tracking

AM-FM models analyze an image in terms of amplitude and frequency modulated sinusoids. Such models are well suited to describe the local non-stationarities of an image. In this paper, the invariance of AM-FM features with respect to scaling, rotation and illumination changes is presented. These properties can be used in applications of AM-FM image models where features for affine transformed images need to be computed. The application of invariance properties in template tracking is illustrated using a particle filter based tracker that uses the AM-FM features.