Application of the watershed boundary technique to automatically segment surface froth images
The purpose of this dissertation is to investigate the suitability of using a recently proposed computer processing algorithm - the watershed boundary technique for applications in computer vision systems, where on-line segmentation of the surface froth images in commercial flotation cells is required. In industrial flotation cells, the surface froth offers considerable visual information as to the grade and recovery in extraction and the concentration of minerals in raw ores. The individual bubbles that constitute the surface froth give rise to complex three-dimensional structures that are problematic to segment accurately and reliably by computer vision. Investigating an efficient technique to automatically and accurately extract these visual features in real time is therefore the main task of this research work. Past research work into this field has resulted in a number of different techniques and algorithms for the purpose of segmentation. However, these algorithms are often iterative and therefore quite slow. The technique described here is noniterative and therefore one with industrial real time processing implications. The results show that the watershed boundary technique provides a reliable method for the segmentation of surface froth structures. Minor errors which occur do not significantly influence the statistical parameters which can be determined from the segmented images. This technique is not only very successful in segmentation, but may also be implemented for real-time operation. This clearly leads to a viable new segmentation method.
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