Video region segmentation by spatio-temporal watersheds

We propose a video region segmentation scheme combining spatio-temporal edges and watershed techniques. We consider the video sequence as a 3-D volume and compute color edges within this volume. These color edges form a vector field that is in turn used to obtain an edge function. This edge function is used as a topological surface for a watershed grouping stage. Considering the video as a 3-D volume results in a batch segmentation instead of the traditional frame-by-frame segmentation. The main advantages of this approach are: 1) exploiting the time continuity in the frame sequence , 2) avoiding problems in tracking regions from frame to frame, 3) using a fast watershed-based method in forming the final video regions. Preliminary experimental results are very promising.