Book Image

Hands-On Generative Adversarial Networks with PyTorch 1.x

By : John Hany, Greg Walters
Book Image

Hands-On Generative Adversarial Networks with PyTorch 1.x

By: John Hany, Greg Walters

Overview of this book

With continuously evolving research and development, Generative Adversarial Networks (GANs) are the next big thing in the field of deep learning. This book highlights the key improvements in GANs over generative models and guides in making the best out of GANs with the help of hands-on examples. This book starts by taking you through the core concepts necessary to understand how each component of a GAN model works. You'll build your first GAN model to understand how generator and discriminator networks function. As you advance, you'll delve into a range of examples and datasets to build a variety of GAN networks using PyTorch functionalities and services, and become well-versed with architectures, training strategies, and evaluation methods for image generation, translation, and restoration. You'll even learn how to apply GAN models to solve problems in areas such as computer vision, multimedia, 3D models, and natural language processing (NLP). The book covers how to overcome the challenges faced while building generative models from scratch. Finally, you'll also discover how to train your GAN models to generate adversarial examples to attack other CNN and GAN models. By the end of this book, you will have learned how to build, train, and optimize next-generation GAN models and use them to solve a variety of real-world problems.
Table of Contents (15 chapters)
Free Chapter
1
Section 1: Introduction to GANs and PyTorch
5
Section 2: Typical GAN Models for Image Synthesis

Pix2pixHD – high-resolution image translation

Pix2pixHD was proposed by Ting-Chun Wang, Ming-Yu Liu, and Jun-Yan Zhu, et. al. in their paper, High-Resolution Image Synthesis and Semantic Manipulation with Conditional GANs, which was an upgraded version of the pix2pix model. The biggest improvement of pix2pixHD over pix2pix is that it supports image-to-image translation at 2,048x1,024 resolution and with high quality.

Model architecture

To make this happen, they designed a two-stage approach to gradually train and refine the networks, as shown in the following diagram. First, a lower resolution image of 1,024x512 is generated by a generator network, , called the global generator (the red box). Second, the image is enlarged...