Book Image

Hands-On Vision and Behavior for Self-Driving Cars

By : Luca Venturi, Krishtof Korda
Book Image

Hands-On Vision and Behavior for Self-Driving Cars

By: Luca Venturi, Krishtof Korda

Overview of this book

The visual perception capabilities of a self-driving car are powered by computer vision. The work relating to self-driving cars can be broadly classified into three components - robotics, computer vision, and machine learning. This book provides existing computer vision engineers and developers with the unique opportunity to be associated with this booming field. You will learn about computer vision, deep learning, and depth perception applied to driverless cars. The book provides a structured and thorough introduction, as making a real self-driving car is a huge cross-functional effort. As you progress, you will cover relevant cases with working code, before going on to understand how to use OpenCV, TensorFlow and Keras to analyze video streaming from car cameras. Later, you will learn how to interpret and make the most of lidars (light detection and ranging) to identify obstacles and localize your position. You’ll even be able to tackle core challenges in self-driving cars such as finding lanes, detecting pedestrian and crossing lights, performing semantic segmentation, and writing a PID controller. By the end of this book, you’ll be equipped with the skills you need to write code for a self-driving car running in a driverless car simulator, and be able to tackle various challenges faced by autonomous car engineers.
Table of Contents (17 chapters)
1
Section 1: OpenCV and Sensors and Signals
5
Section 2: Improving How the Self-Driving Car Works with Deep Learning and Neural Networks
12
Section 3: Mapping and Controls

Summary

This has been a very practical chapter, showing one way to proceed when training a neural network. We started from a big model, achieving 69.7% validation accuracy, and then we reduced its size and added some layers to increase the number of non-linear activations. We used batch normalization to equalize the contribution of all the channels and then we learned about early stopping, which helped us to decide when to stop the training.

After learning how to automatically stop the training, we applied it immediately with data augmentation, which increases not only the size of the dataset but also the number of epochs required to properly train the network. We then introduced Dropout and SpatialDropout2D, a powerful way to reduce overfitting, though not always easy to use.

We ended up with a network achieving 87.8% accuracy.

In the next chapter, we will train a neural network that will be able to drive a car on an empty track!