PNG Format

PNG - Portable Network Graphic format (pronounced "ping")
Developed as an alternative to GIF and JPEG

• Requires Internet Explorer Version 4.0 or greater, Netscape Navigator 4.0.4 or better
• 8-bit and 24-bit support
• enhanced resolutions of 16-bits (gray scale) and 48 bits (true color) per pixel, and up to 16 bits of alpha data.
• lossless compression
• create and use up to 8-bit masks, allows for variable transparency
• Gamma control, which gives cross-platform consistency of image brightness.
  Macs have a gamma of about 1.8 and PCs a gamma of 2.2. Graphics that look great on a Macintosh often look dark on a PC.
• interlacing preview support after only 1/64 of image downloaded.
• Better than JPEG for photos with fine detail (such as lines).
• 8-bit version yields slightly smaller file sizes than GIF
• 24-bit version file size are much larger than JPEG files due to the fact that PNG is lossless
  For example, a PNG-24 file of about 350k, will often compress to 25k Jpeg (30 quality).

Topics