Improving Citrus Fruit Classification with X-ray Images Using Features Enhanced Vision Transformer Architecture

Abstract

Quality assessment is a cornerstone of fruit production and distribution, particularly regarding storage conditions and duration. Citrus fruits, a staple in global consumption patterns, are the ultimate example. This study employs a nondestructive analytical technique, X-ray computed tomography (CT) scanning, to meticulously analyze a substantial sample of 300 citrus fruits, specifically satsuma, subjected to both ambient (20–22 °C, 50–60% humidity) and refrigeration conditions (6–8 °C, 65–75% humidity). The experiment was conducted through a methodologically rigorous approach, stratified dataset splitting, allocating 60% of the X-ray datasets for training, with 20% dedicated to validation and testing, respectively. The proposed research introduces a pioneering methodology termed features enhanced vision transformer (FEViT), meticulously designed to augment precision in citrus fruit classification and more precise freshness level prediction via X-ray image analysis. Our empirical findings unequivocally demonstrate the superior efficacy of FEViT models vis-a-vis conventional ViT counterparts across new X-ray citrus fruit datasets. Particularly noteworthy are the marked performance gains exhibited by FEViT-large variants, evidenced by notable increases in precision (5.08%), accuracy (5.47%), recall (4.55%), and F1 scores (5.28%) over original variants. This underscores the distinguishable enhanced discriminatory prowess of FEViT models in assessing citrus fruit quality in terms of freshness. Extensive validation through rigorous experimentation ratifies FEViT’s supremacy over traditional deep learning architectures, affirming heightened accuracy (99.25%). The current study heralds the advent of FEViT architecture as a milestone in citrus fruit (satsuma) freshness prediction, promising augmented accuracy and robustness vis-a-vis extant methodologies. This research holds profound implications for the agricultural sector, especially in domains such as citrus and broader fruit classification, where nuanced image analysis is indispensable for quality attribute like freshness evaluation and informed decision-making.