fruit class or not. A reference table was created for various classes with the Bayesian

classification technique.

 Casasent et al. (1996) used X-ray images to detect and segment multiple touching

pistachio nuts placed on a conveyor trays for product inspection. New techniques were

developed for identifying items irrespective of orientation by employing rotation-

invariant filters to locate nuts. Watershed transformation was utilized for segmenting

touching or overlapping nuts. Watershed transform is a region-based segmentation

approach to partition the image into disj oint regions, such that the regions are

homogeneous with respect to some property, such as gray value or texture. Advanced

morphological image processing operations were used to produce gray scale images of

only the nutmeat and to determine the amount of shell area filled by nutmeat.

 Shatadal et al. (1995) developed an algorithm to segment connected grain kernels

i n an i mage to as si st i n a m achi ne vi si on-b as ed-grai n-gradi ng exp eri ment. A

mathematical morphology-based algorithm was developed for disconnecting the

connected kernel regions. The algorithm was used on wheat, durum wheat, barley, oats,

and rye. The only limitation of the algorithm was that it failed when the connected

kernels formed a relatively long isthmus between them.

 The maj ority of these works used charge coupled device (CCD) cameras to capture

images and to use local or shape-based analysis to detect fruit. A CCD is a silicon chip

whose surface is divided into light-sensitive pixels. When a photon (light particle) hits a

pixel, it registers a tiny electric charge that can be counted. With large pixel arrays and

high sensitivity, CCDs can create high- resolution images under a variety of light

conditions. A CCD camera incorporates a CCD to take such pictures. Systems based on