UCSC-CRL-02-39: FAST REGION MERGE PROCESSING FOR WATERSHED TRANSFORMS

12/12/2002 09:00 AM
Electrical Engineering
Controlling the Watershed Transform\'s (WST) tendency to oversegment images is a major concern in published WST applications. Gradient magnitude thresholding (GMT) is the primary tool used to control WST segmentation due to its relatively fast and simple implementation. In this paper, we describe a new method to control WST oversegmentation which we refer to as drainage simulation-based region merging. The drainage simulation is applied after the WST and provides a mechanism for the fast merging of regions without requiring the updates of existing region descriptors. The new technique controls WST oversegmentation in the image areas containing the highest spatial frequencies. Similar to GMT, applying drainage simulations are automatic in that they require no outside user intervention. The results show that the region count in the partitioned image is significantly reduced by utilizing drainage simulation-based region merging. These results are produced after an application of GMT using a relatively low threshold value. The results likewise indicate that important edge information from the original image is not compromised by the drainage simulation-based region merging.

UCSC-CRL-02-39