Robust global motion estimation using a simplified M-estimator approach

Global motion estimation is an important task in a variety of video processing applications, such as coding, segmentation, classification/indexing or mosaicing. Due to the possible presence of differently moving foreground objects and other sources of distortions, robust methods such as M-estimators have to be applied. We present a simplified implementation of a robust M-estimator for global motion estimation that does not increase the computational complexity significantly compared to a non-robust estimator, while providing excellent results in terms of estimation accuracy. Additionally, unstructured image regions are detected and rejected for the estimation. This avoids aperture problems, that can have an bad impact especially on robust estimators that rely on a certain error measure.