High Performance Images: Shrink, Load, and Deliver Images for Speed

High-quality images have an amazing power of attraction. Just add some stunning photos and graphics to your website or app and watch your user engagement and conversion numbers climb. It can be tricky, but with this practical guide, you’ll master the many facets of delivering high performance images on the internet—without adversely affecting site performance.

You’ll learn the nuts and bolts of color theory, image formats, storage and management, operations delivery, browser and application behavior, the responsive web, and many other topics. Ideal for developers, this book also provides useful tips, tricks, and practical theory for processing and displaying powerful images that won’t slow down your online product.

• Explore digital image theory and the different formats available
• Dive into JPEGs, SVG and vector images, lossless compression, and other formats
• Use techniques for downloading and rendering images in a browser, and for loading images on mobile devices and cellular networks
• Examine specific rendering techniques, such as lazy loading, image processing, image consolidation, and responsive images
• Take responsive images to the next level by using content negotiation between browser and server with the Client Hints HTTP standard
• Learn how to operationalize your image workflow

Contributors include Colin Bendell, Tim Kadlec, Yoav Weiss, Guy Podjarny, Nick Doyle, and Mike McCall from Akamai Technologies.

Table of Contents

Chapter 1. The Case for Performance

Part I. Image Files and Formats
Chapter 2. The Theory Behind Digital Images
Chapter 3. Lossless Image Formats
Chapter 4. JPEG
Chapter 5. Browser-Specific Formats
Chapter 6. SVG and Vector Images

Part II. Image Loading
Chapter 7. Browser Image Loading
Chapter 8. Lazy Loading
Chapter 9. Image Processing
Chapter 10. Image Consolidation (for Network and Cache Efficiencies)
Chapter 11. Responsive Images
Chapter 12. Client Hints
Chapter 13. Image Delivery
Chapter 14. Operationalizing Your Image Workflow
Chapter 15. Summary

Appendix A. Raster Image Formats
Appendix B. Common Tools
Appendix C. Evolution of