PNG is an elegant and feature-rich image format that has recently achieved broad industry support. PNG is supported by major software applications like Macromedia Fireworks, Adobe Photoshop, Microsoft Office, Netscape Navigator, and Microsoft Internet Explorer. "It takes about four years--sometimes more--for a new computer image format to become widely accepted" says Roelofs. "This was true of GIF, TIFF, JPEG/JFIF and now PNG, and it will presumably hold for newcomers such as JPEG 2000 and the W3C's vector format, SVG. Since this effect was first observed by Tom Lane--principal author of libjpeg, member of the TIFF Advisory Committee, and another of PNG's designers--I refer to it as "Lane's Law of Image Formats."

PNG is similar to the GIF and TIFF formats, but with a number of designer-friendly improvements. It is anticipated to quickly become the preferred file format for color-critical web images and high-quality graphics interchange. And because of features such as lossless compression, alpha transparency (variable levels of transparency), and a wide range of color depths, PNG is expected to supplant GIF as the standard web format for even non-critical images. Even animated GIFs may soon be replaced by MNG, which is the animated version of PNG and which was just recently frozen as a specification (Roleofs covers the MNG in Chapter 12 of his new book). PNG also provides direct support for gamma correction, the cross-platform control of image "brightness," and embedded text annotations such as author and copyright info.

PNG: The Definitive Guide is the first book devoted exclusively to teaching and documenting this important new format. It is an indispensable compendium for Web content developers and is full of examples, application information, and practical hands-on advice. PNG: The Definitive Guide is also essential for programmers who want to add full PNG support their own applications. It focuses on implementing PNG with the libpng C library and steps through three complete demo programs, discussing key elements of each and noting alternative approaches wherever appropriate. The book includes explanations of important improvements with PNG, such as gamma correction and the standard color spaces for precise reproduction of image colors on a wide range of systems.

"The PNG format is one step in the evolution of portable, robust image formats. With good, ubiquitous support just around the corner in web browsers, and support in image-viewing and editing applications not merely common but actually expected by customers, PNG's future is bright," says Roelofs.

For more information about the book, including Table of Contents, index, author bio, and sample chapter, see: http://www.oreilly.com/catalog/pngdefg/

###