Temporal motion vector filtering

Methods and apparatus, including computer program products, implementing and using techniques for performing temporal motion vector filtering in digital video are disclosed. A recursive hierarchical process is used to determine a motion vector. In the recursive hierarchical process, a neighborhood of old motion vectors is filtered to generate a first estimated motion vector for an image patch in a pair of two image frames. The filtering process uses multiple vectors in a neighborhood around the old motion vector to improve the prediction of the first estimated motion vector. The temporal vector partitioning process separates motion vectors associated with an object from motion vectors associated with a background before selecting a best motion vector, which improves the selection process. The process also works well in the absence of object / background boundaries, as in this case the outlier (incorrect) vector or vectors will be separated out from the good vectors.