Study On Multi-angle Hyperspectral Polarization Detection Model Of Red Jujubes In Southern Xinjiang

In order to improve the accuracy and efficiency of the rapid detection model of jujubes in southern Xinjiang,multi-angle polarization calibration and calibration experiments were carried out.Using the polarization dichroism measurement system,the height angles of different light sources,the azimuth angles of different detectors,and the azimuth angles of different polarizers were used to measure the reflectivity of red jujubess and leaves.At the same time,using hyperspectral sorting instrument,the hyperspectral data of different growth stages of red jujubess,different polarization angles,indoor dark box and outdoor jujubess were collected.Finally,the water content of the indoor red jujubess hyperspectral data was modeled by different spectral data processing methods using different modeling methods.At the same time,the hyperspectral polarization detection system was upgraded.The main conclusions are summarized as follows:(1)Measuring the azimuth angle(0°-360°)of the blade and red jujubes by the polarization dichroic reflection measurement system,the height angle of the light source(30°,40°,50°,60°),and the height angle of the detector(0)°,10°,20°,30°,40°,50°,60°),degree of polarization(0°,90°)reflectance of the sample,which can be seen when the azimuth angle is 0°~100° and 200°~250° The reflectance value changes little,and the leaves and red dates show Lambert characteristics in this interval.Significant reflection peaks occur when the azimuth angle is 150°(hot spot).At the same time,the detector's 0°polarization reflectance is higher than 90° polarization at the same height.(2)120 red jujubess were measured in the laboratory by hyperspectral sorter.The spectral data of jujubes were pre-treated by ENVI software to extract the region of interest,and the moisture content of jujubes was calculated by drying and mass reduction method.Model The data model were established by using TQ.Through different preprocessing methods,the optimal model can be obtained by using the partial least squares method to smooth the MSC and the first derivative.In the model,R is 0.92816,the SEC is 0.248,the SEP is 0.482.The number of principal factors is 10.(3)Using the polarization function of the hyperspectral detection system to measure the high-spectral polarization data at different angles in the outdoor,and applying the Stokes parameter expression to calculate the high-spectral polarization image to obtain S0,S1,S2,linear polarization degree DoLP,polarization phase angle Orient image.The fifth-order polynomial model of the polarization component was established,and the hnd 3.9971,respectively.(4)Using the ENVI hyperspectral Pop library management tool to establish a red jujubes background spectral library and a target polarization spectrum library.The known pops were analyzed using a pop analysis in the establishment of the target polarization spectrum.The results were found to be 0.852,0.824,0.924,and 0.943,respectively.It can be seen that Popper library is suitable for classification and prediction identification of spectra.