■对薄皮水果瘀伤的无损检测是收获后水果自动分级的主要挑战之一。结构照明反射成像(SIRI)是一种新兴的光学技术,具有检测瘀伤的潜力。
■这项研究提出了低成本可见光LEDSIRI在检测\'Korla\'梨早期皮下瘀伤中的开创性应用。三种类型的瘀伤程度(轻度,中度和重度)和十组空间频率(50、100、150、200、250、300、350、400、450和500个周期m-1)进行了分析。通过评估对比指数(CI)值,150个周期m-1被确定为最佳空间频率。对正弦图像进行解调以获得DC,AC,和RT图像没有任何条纹信息。基于AC和RT图像,提取纹理特征,利用LS-SVM,PLS-DA和KNN分类模型结合了优化的功能,用于检测具有不同程度瘀伤的“库尔勒”梨。
■发现无论模型类型如何,RT图像始终优于AC图像,LS-SVM模型表现出最高的检测精度和稳定性。穿过温和,中度,严重和混合的瘀伤,具有RT图像的LS-SVM模型的分类准确率为98.6%,98.9%,98.5%,98.8%,分别。这项研究表明,可见光LEDSIRI技术可以有效地检测\'库尔勒\'梨的早期瘀伤,为利用低成本可见光LEDSIRI检测水果危害提供了有价值的参考。
UNASSIGNED: Nondestructive detection of thin-skinned fruit bruising is one of the main challenges in the automated grading of post-harvest fruit. The structured-illumination reflectance imaging (SIRI) is an emerging optical technique with the potential for detection of bruises.
UNASSIGNED: This study presented the pioneering application of low-cost visible-LED SIRI for detecting early subcutaneous bruises in \'Korla\'
pears. Three types of bruising degrees (mild, moderate and severe) and ten sets of spatial frequencies (50, 100, 150, 200, 250, 300, 350, 400, 450 and 500 cycles m-1) were analyzed. By evaluation of contrast index (CI) values, 150 cycles m-1 was determined as the optimal spatial frequency. The sinusoidal pattern images were demodulated to get the DC, AC, and RT images without any stripe information. Based on AC and RT images, texture features were extracted and the LS-SVM, PLS-DA and KNN classification models combined the optimized features were developed for the detection of \'Korla\'
pears with varying degrees of bruising.
UNASSIGNED: It was found that RT images consistently outperformed AC images regardless of type of model, and LS-SVM model exhibited the highest detection accuracy and stability. Across mild, moderate, severe and mixed bruises, the LS-SVM model with RT images achieved classification accuracies of 98.6%, 98.9%, 98.5%, and 98.8%, respectively. This study showed that visible-LED SIRI technique could effectively detect early bruising of \'Korla\'
pears, providing a valuable reference for using low-cost visible LED SIRI to detect fruit damage.