Page 174 - Handbook of Deep Learning in Biomedical Engineering Techniques and Applications
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Chapter 6 Plant leaf disease classification based on feature selection  163





























                                 Figure 6.7 AlexNet architecture.


                  The convolutional layers are split to contain mapped kernels
               in the same graphical processing units. The convolutional layers
               reduce the image parameters producing 4096 dimensional
               features for the FC layer that are mapped into a logistic regression
               output containing 1000 classes. This architecture uses various
               kinds of transformations for data augmentation to increase
               learning. These spatial transforms provide more robust training
               samples for the network.
               3.3.2 VGG16 (2014)
                  VGGNet [15] is a neural network that performed extremely well
               in the ImageNet Large Scale Visual Recognition Challenge
               (ILSVRC) in 2014. This architecture is from VGG group, Oxford.
               It makes the enhancement over AlexNet by replacing expensive
               kernel size filters with various 33 filters in a steady progression.
               Fig. 6.8 shows the VGG16 architecture.
                  This idea of blocks/modules was introduced in VGG. The
               VGG convolutional layers are trailed by three FC layers. The
               width of the filters begins with 64 and increments by a factor
               of 2 after each pooling layer. The images in the challenge were
               divided into 1000 unique classes. Given a test image, the VGG
               network determines a likelihooddin the range of 0 and 1dfor
               every one of those 1000 classes and selects the class with the
               highest likelihood.
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