Fig. 5.

Overlap between sets of spectra with different absorbers for eight preprocessing algorithms. The axes are labeled with the type of absorbers included, where B, blood; W, water; F, fat; and Bi, bilirubin. SNV, MSC, and AUC reduce the overlap the most, followed by MM, which reduces the overlap less than SNV, MSC, or AUC but still reduces the overlap significantly. MC reduces the overlap less. Finally, FD, SD, and SW reduce the overlap the least with some high values for a few combinations remaining.