Shape Analysis of Agricultural Products: A Review of Recent Research Advances and Potential Application to Computer Vision

Abstract

The appearance of agricultural products deeply conditions their marketing. Appearance is normally evaluated by considering size, shape, form, colour, freshness condition and finally the absence of visual defects. Among these features, the shape plays a crucial role. Description of agricultural product shape is often necessary in research fields for a range of different purposes, including the investigation of shape traits heritability for cultivar descriptions, plant variety or cultivar patents and evaluation of consumer decision performance. This review reports the main applications of shape analysis on agricultural products such as relationships between shape and: (1) genetic; (2) conformity and condition ratios; (3) products characterization; (4) product sorting and finally, (5) clone selection. Shape can be a protagonist of evaluation criteria only if an appreciable level of image shape processing and automation and data are treated with solid multivariate statistic. In this context, image-processing algorithms have been increasingly developed in the last decade in order to objectively measure the external features of agricultural products. Grading and sorting of agricultural products using machine vision in conjunction with pattern recognition techniques offers many advantages over the conventional optical or mechanical sorting devices. With this aims, we propose a new automated shape processing system which could be useful for both scientific and industrial purposes, forming the bases of a common language for the scientific community. We applied such a processing scheme to morphologically discriminate nuts fruit of different species. Operative Matlab codes for shape analysis are reported.

Influence of Contact Surface Type on the Mechanical Damages of Apples Under Impact Loads

“…Key parameters in assessing this phenomenon include impact level necessary to calculate the impact energy and volume of deformed tissue. This measurement of bruise volume is considered as an independent way if the bruised surface resembles a circular or elliptical shape (Costa et al 2011). In the literature, the following methods to measure bruise volume were up till now used: bruise thickness method (Mohsenin 1986), full-depth method (Saltveit 1984), enclosed volume (Holt and Schrool 1977), unbruised volume removed (Pang et al 1992), and ellipsoid (Hung and Prussia 1989).…”

Seed curvature as a useful marker to transfer morphologic, agronomic, chemical and sensory traits from Ganxet common bean ( Phaseolus vulgaris L.)

“…In Catalonia, the historical home of Ganxet cultivation, 257 entries with different agricultural and morphological characteristics have been collected (Rull et al, 2012) and are conserved in the FMA-BarcelonaTech germplasm bank. Seed shape, size, and seed-coat color are important in consumers' preferences and market acceptance (Costa et al, 2011;Mkanda et al, 2007). The study of these traits goes back to the beginning of the twentieth century, with Johannsen's landmark study on size (Johannsen, 1903).…”

“…Seed shape, size, and seed-coat color are important in consumers' preferences and market acceptance (Costa et al, 2011;Mkanda et al, 2007). The study of these traits goes back to the beginning of the twentieth century, with Johannsen's landmark study on size (Johannsen, 1903).…”

Hybrid Drying of Carrot Preliminary Processed with Ultrasonically Assisted Osmotic Dehydration

“…It is also worth noticing that colour of the product surface is the first quality parameter evaluated by consumers, and it is critical to product acceptance (25)(26)(27). Colour is the first sensation that the consumers perceive, thus it has a strong influence on their opinion about the food quality (28).…”