Fig. 5: NIR-HSI results for sample BRA-3367.

a Grey-scale total intensity image; b PLS map of the reference samples. The colour bar numbers refer to collagen % predicted by the PLS model. The red square area is the selected sample taken for the extraction of collagen; c–e ROIs referring to areas with different collagen concentrations (blue: low, green: mid-level, red: high) on an individually scaled map.