Fig. 2.

Stepwise diagrammatic representation of transfer learning by Chowdhury et al. [46]. The first step is the acquisition of the patients' data from an X-ray imaging machine. Both two-class classification and three-class classification are performed. Second, in the image resizing (preprocessing) step, the input layer of the deep learning method is fit. Data augmentation is performed in one of the experiments. Then, transfer learning is performed on various deep learning architectures. Finally, the trained model is saved, and classification is performed.