基于高光谱成像提取苹果糖度与硬度最佳波长  

Optimal Wavelengths Extraction of Apple Brix and Firmness Based on Hyperspectral Imaging

作　　者：冯迪[1,2] 纪建伟[1] 张莉 刘思伽[1] 田有文[1] 

机构地区：[1]沈阳农业大学信息与电气工程学院,辽宁沈阳110866 [2]辽宁广播电视台,辽宁沈阳110004 [3]辽宁广播电视传输发射中心,辽宁沈阳110004

出　　处：《发光学报》2017年第6期799-806,共8页Chinese Journal of Luminescence

基　　金：辽宁省大型仪器设备共享服务项目(LNDY201501003);沈阳市大型仪器设备共享服务专项项目(F15-166-4-00)资助~~

摘　　要：利用高光谱成像技术提取可同时检测苹果糖度与硬度的最佳波长。首先双面采集苹果的高光谱图像,获取亮度相近感兴趣区域(ROIs)的反射波形,采用二阶导数结合标准正态变量(SD+SNV)的方法平滑波形,测试ROIs的糖度与硬度;之后采用连续投影算法(SPA)提取两项指标的特征波长,根据特征波长的分布提出二次连续投影算法,结合波形集特征与两次投影结果确定不同取样面的最佳波长;最后采用遗传算法开发神经网络(GA-BP)建立预测模型,双面取样波长(543 nm和674 nm)效果最优,糖度相关系数(R)为0.847 6,均方误差(MSE)为3.32;硬度R为0.793 8,MSE为9.6。结果表明,相同波长信息可以检测苹果糖度与硬度。Hyperspectral imaging technology was brix and firmness test. Firstly, the hyperspectral used to extract the optimal wavelength for apple images of apples were acquired from double-sided sampling. The reflection waveforms of the regions of interest （RIOs） with similar brightness were ac- quired and smoothed by the second derivation and standard normal variate （ SD ＋ SNV ） method. The brix and firmness values of RIOs were also tested. Then, the characteristic wavelengths of two indicators were extracted by using the successive projections agorithm（SPA）. According to the dis- tribution of characteristics wavelengths, two times SPA was proposed. Combined the feature of wave- forms and the results of two projections, the optimal wavelengths of different sampling facets were determined. Finally, the genetic algorithm for back propagation（GA-BP） was used to build the pre- diction model. The best results were obtained from the double-sided sampling wavelengths （543 nm and 674 nm）. The correlation coefficient of brix （R） is 0. 847 6 and the mean square error （MSE） is 3.32, and for the firmness, R is 0. 793 8 and MSE is 9.6. The results show that the brix and firmness can be detected by the same wavelength information.

关 键 词：高光谱成像 苹果 最佳波长 二次连续投影算法 遗传算法开发神经网络 

分 类 号：S126[农业科学—农业基础科学] TP391.44[自动化与计算机技术—计算机应用技术]