Watershed and adaptive pyramid for determining the apple´s maturity state

A new method of image processing, developed within the framework of the automatic evaluation of the state of maturity of fruit, is presented. It has been shown that maturity spots can be seen on images of fruit obtained by laser-induced fluorescence. The presented method is able to detect and to quantify these spots automatically. The initial image processing is provided by a watershed algorithm. In order to refine the obtained segmentation, a multiresolution method is developed. It is based on the representation of data with an adaptive pyramid of region adjacency graphs (RAG) associated with a multi-criteria approach. This approach allows regions to be merged and only the information corresponding to the maturity spot to be stored. Interesting experimental results have been obtained on a set of 20 images of apples.