Graphics Formats for the WWW: PNG

• PNG is a lossless, portable, well-compressed RGB file format that can include mask-channel information.

• Progressive display for on-line use.

• Higher compression rates PNG uses better image compression technology than GIF, allowing for smaller files that download more quickly

• Higher bit depths (more colors) PNG allows for 1, 2, 4, 8, 16, 24 and 32 bit images, smashing the 8-bit barrier

• A permanent, royalty-free license PNG is being developed by the W3C, and will always be a free and open standard

• Multiple layers of transparency PNG images allow for full alpha channel transparency, which makes moving images from one background to another easy

• Built-in gamma correction. PNG can store gamma and chromaticity data for improved color matching on heterogeneous platforms. Users can see an image the way it was intended to be seen by selecting the gamma level intended for their monitor.

Resources

• The Official PNG Hompage:
  A comprehensive PNG resource, covering everything from image converters to free source code for building your own PNG applications.

• Adobe File Utilities:
  Adobe has created a wonderful package for creating and converting images among many file formats, including PNG.

• ACK Software's Pixsoft:
  This is a great utility for creating PNG images on the Windows 95 and Windows NT platforms.

• News from the PNG Group:
  This is the place to see all of the important news in the PNG development community.

• Introduction to Gamma:
  Here is an excellent introduction to the concept of gamma correction, and how it applies to computer graphics.

• Making Pictures for the Web:
  Here is another excellent tutorial on making images clearer for online presentation.

• PNG Plug-in for Photoshop
  Infinop have created a great shareware plug-in that will allow you to create PNGs on a Macintosh in seconds flat.

• CNET News Story
  Check out the CNET's story on the adoption of PNG and the World Wide Web Consortium's postion on the standard.