Figure 4.

Data processing and data analysis of MSI data. MSI data are preprocessed after acquisition. This process includes several steps including spectra normalization, baseline correction, smoothing, and recalibration. Next, MSI data will undergo compression and representation, which reduces the computational load. Then data analysis could be completed, including peak picking and other statistical analyses, such as classification, principal component analysis (PCA), spatial segmentation, and others. Machine learning is a popular method used in these analyses. Postprocessing includes magnification and coregistration of the images. Adapted with permission from Ref. (29). Copyright (2018) American Chemical Society. MSI, MS imaging.