Abstract
A remote measuring method for volumes of fruit like rotational bodies was developed using digital images, and the precision of this method was examined using detached fruits. Further, based on these principles, remote measurement of volumes of attached fruits in an apple cultivar and a pear were carried out seasonally using several types of field photography devices. Each coordinate on a fruit outline in a side photograph was read in pixel units along the fruit shaft using an image analysis program. The volume of each very thin rotational disk composed of each radius and one pixel thickness was calculated and totaled. Cavity volumes were similarly calculated from cavity outlines in other images photographed at a 45-degree angle. The latter was used to deduce the fruit volume from the former. The relations between the measured volumes and the remote measured volumes were fairly good in several cultivars of apple, pear and grape. Photography for remote measuring in the field became possible using a device that allowed regulation of the height and angle in simultaneous photographs from two directions and maintained the attitude of cameras at 45 degrees.
