pngquant is a command-line^* utility to quantize and dither 32-bit RGBA PNGs down to 8-bit (or smaller) RGBA-palette PNGs, usually with a significant reduction in file size. (Other PNG image types, even colormapped images, may also be processed, but they will first be expanded to RGBA, which isn't the most efficient way to do so.) This is the same technique used for many of the images on the Miscellaneous Transparent PNGs page, and the results are often indistinguishable from the original, truecolor PNG images.

^*Per Fahlén and Jens Wedin have recently made available a Windows GUI wrapper for pngquant (binary only).

Version 1.0 supports batch processing (i.e., wildcard multifile capability: ``pngquant 256 *.png''), palette (tRNS) optimization, and Unix-style filter operation (e.g., ``make_RGBA_png | pngquant 48 | some_other_command''), and it compiles and runs on both Linux and Win32 without obvious problems. The only difference from the previous release, 0.95, is the addition of a clean target to the Unix makefile.

• PNG home page
• MNG home page

Copyright © 2000-2005 Greg Roelofs.