METHOD AND APPARATUS FOR HIERARCHICAL MOTION ESTIMATION USING DFD-BASED IMAGE SEGMENTATION

摘要

In hierarchical motion estimation, in each motion estimation hierarchy level, a pixel block matcher for comparing correspondingly sampled pixel values of a current image and a delayed previous image is used in order to compute a motion vector for every pixel. By evaluating displaced frame differences in the measurement window, a segmentation of the measurement window into different moving object regions is performed. The corresponding segmentation information is stored, and the stored segmentation information is used as an initial segmentation mask for motion estimation in the following finer level of the motion estimation hierarchy. In the following finer level of the motion estimation hierarchy an updated segmentation information is determined. This processing continues until the finest level of said motion estimation hierarchy is reached. The resulting segmentation information values of successive search window positions can be combined.

主权项

1. A method for hierarchical motion estimation, including:
a) using—in each motion estimation hierarchy level—in a pixel block matcher of a corresponding motion estimator a measurement window for comparing correspondingly sampled pixel values of a current image frame and a delayed previous image frame in order to compute a motion vector for every pixel of interest, determining a segmentation information representative of segmentation of the measurement window into different moving object regions, wherein said segmentation information comprises a per-pixel segmentation mask and wherein a segmentation information value for a pixel is assigned to a moving object region in case where a displaced frame difference resulting from an optimum motion vector in the measurement window is larger a threshold; b) storing corresponding segmentation information; c) using said stored segmentation information as an initial segmentation for motion estimation in the following finer level of the motion estimation hierarchy; d) determining in said following finer level of the motion estimation hierarchy an updated segmentation information based on a remaining displaced frame difference resulting from the optimum motion vector of said stored segmentation information; e) continuing the processing with steps b) to d) until the finest level of said motion estimation hierarchy is reached.