Book Image

Practical Convolutional Neural Networks

By : Mohit Sewak, Md. Rezaul Karim, Pradeep Pujari
Book Image

Practical Convolutional Neural Networks

By: Mohit Sewak, Md. Rezaul Karim, Pradeep Pujari

Overview of this book

Convolutional Neural Network (CNN) is revolutionizing several application domains such as visual recognition systems, self-driving cars, medical discoveries, innovative eCommerce and more.You will learn to create innovative solutions around image and video analytics to solve complex machine learning and computer vision related problems and implement real-life CNN models. This book starts with an overview of deep neural networkswith the example of image classification and walks you through building your first CNN for human face detector. We will learn to use concepts like transfer learning with CNN, and Auto-Encoders to build very powerful models, even when not much of supervised training data of labeled images is available. Later we build upon the learning achieved to build advanced vision related algorithms for object detection, instance segmentation, generative adversarial networks, image captioning, attention mechanisms for vision, and recurrent models for vision. By the end of this book, you should be ready to implement advanced, effective and efficient CNN models at your professional project or personal initiatives by working on complex image and video datasets.
Table of Contents (11 chapters)

AlexNet architecture

The first breakthrough in the architecture of CNN came in the year 2012. This award-winning CNN architecture is called AlexNet. It was developed at the University of Toronto by Alex Krizhevsky and his professor, Jeffry Hinton. 

In the first run, a ReLU activation function and a dropout of 0.5 were used in this network to fight overfitting. As we can see in the following image, there is a normalization layer used in the architecture, but this is not used in practice anymore as it used heavy data augmentation. AlexNet is still used today even though there are more accurate networks available, because of its relative simple structure and small depth. It is widely used in computer vision:

AlexNet is trained on the ImageNet database using two separate GPUs, possibly due to processing limitations with inter-GPU connections at the time, as shown in the...