Hyperspectral imaging for textile sorting in the visible–near infrared range

Recycling of textile materials is becoming important due to the increasing amount of textile waste and its largeenvironmental impact. The Resyntex project aims at dealing with this textile waste by enabling its chemical recycling. To do so, pure textile materials and blends need to be sorted first. In this paper we evaluate the suitability of hyperspectralimaging for pure and blend textile sorting. We also test the discrimination capacity between denim and non-denim textile,since this is required prior to the de-colouration processes. For this purpose, we use a line-scan sensor in the 450–950nm range, since its cost, compactness and speed characteristics make it suitable for industrial deployment. To deal withthe strong colour interference of the textile a hierarchical classification approach is proposed. The results on the availablesample set show promising discrimination potential for material discrimination as well as for denim versus non-denimdetection.