WEIGHING FLOWERS AS AN ALTERNATIVE METHOD FOR SORTING BY VISUAL APPEARANCE

The relationship between mass and visual appearance of flowers that ar e used as volume and background fillers in bouquets was studied. The m ain objective was to test whether weighing flowers could be used as a simple method for sorting, equivalent to doing so by their visual appe arance, which is the combined impression made by a flower's dimensions , number of stems and leaves, and their density. Two methods of evalua ting the visual appearance of flowers were used: (1) a qualitative and subjective method using an averaged decision made by a panel of human inspectors; (2) a quantitative and objective method using a computer vision system to acquire and analyse two video images of each flower, from perpendicular directions. It was found that human vision could cl early classify flowers as ''small'' or ''big'' according to their visu al appearance. Classifying the flowers into two mass-classes (''light' ' and ''heavy'') closely matched the two-way human vision classificati on (''small'' and ''big''), based on the average decision of the panel of inspectors. On the basis of the averaged panel decisions, flowers of ''light'' and ''heavy'' classes looked more uniform when viewed sep arately than when viewed together. Flower mass correlated well with th e average image area measured by the computer vision system. Based on these results it was concluded that the flowers studied could be class ified by mass to achieve better uniformity of visual appearance. (C) 1 996 Silsoe Research Institute