Visual features such as colour and size indicate the quality of many prepared
consumer foods. Sun (2000) investigated this in research on pizza in which pizza
topping percentage and distribution were extracted from pizza images. A new
segmentation algorithm was developed by combining three algorithms used to
segment many different types of pizzas as the traditional segmentation techniques
were found to be inadequate for this application. Fig. 3(a) and (b) shows a sample
image before and after segmentation using the new algorithm. It was found that the
new region-based segmentation technique could effectively group pixels of the same
topping together. As the result, topping exposure percentage can be easily
determined. The study reported that the accuracy of measuring the topping
percentage by the new algorithm reached 90%.