Fig. 14From: Convolutional neural networks: an overview and application in radiologyAn example of a class activation map (CAM) [58]. A CNN network trained on ImageNet classified the left image as a “bridge pier”. A heatmap for the category of “bridge pier”, generated by a method called Grad-CAM [59], is superimposed (right image), which indicates the discriminative image regions used by the CNN for the classificationBack to article page