An image data processing method includes receiving frame image data of N frames, where N>1, detecting a region of interest in one of the N frames, tracking locations of the region of interest in at least one of the N frames, and providing a merged location of the region of interest based on the locations of the region of interest in the N frames. Some embodiments include providing T of the merged locations of the region of interest for T respective groups of N frames, where T>1, providing respective statistical data for each of the T merged locations, and providing a final location of the region of interest based on the T merged locations and the statistical data for the T merged locations.