The PNG Guide is an eBook based on Greg Roelofs' book, originally published by O'Reilly.

Other Conversion Programs

The converters we've discussed so far barely scratch the surface of what is available. If one includes image editors and viewers that can convert images in addition to dedicated conversion tools, there are well over one hundred applications capable of converting to and from the PNG format.[38b] Many of these were listed in the previous two chapters and are well worth considering, particularly for users who may be uncomfortable dealing with command-line programs.

[38b] As of mid-2003, the number has more than doubled; the PNG home site lists all of them. Perhaps not surprisingly, however, the five discussed above are still among the best.

Here is a list of some of the other dedicated (or nearly dedicated) image converters that support PNG. The most recent version as of January 1999 is given wherever possible.


Version of April 3, 1997, Julian Highfield. Available as an OpenDoc part for Mac 68k/PPC (mostly tested with OpenDoc 1.1 and Mac OS System 7.1.2); read/write support for PNGs.

Version 3.22, John Kortink. Available for Acorn RISC OS; read/write support for PNGs; no alpha or gamma support.

Version 1.8, Sébastien Barré. Available for Windows 9x/NT, Linux x86, SunOS/Solaris SPARC; write-only support for PNGs; supports conversion of 12-bit medical formats to 16-bit grayscale PNGs.

Version 5.50, Aladdin Enterprises. Available for Unix, VMS, OS/2, Windows 9x/NT, and Mac 68k/PPC; older versions available for Windows 3.x, DOS, Amiga, Atari, and possibly Acorn RISC OS; write-only support for PNGs.

Version of February 13, 1997, Neil Aggarwal. Available for any platform supporting Java 1.1 or later; write-only support for PNGs.
Icons Control 95

Version 7.02, Chris Doan. Available for Windows 9x/NT; read-only support for PNGs (converts various image formats to Windows .ico format).
Image Arithmetic

Version 2.2a, Richard van Paasen. Available for Windows 9x/NT; read/write support for PNGs.

Version III v6, Stefan Schneider Software. Available for NeXTStep/OpenStep on 68k/x86/HP-PA/SPARC; write-only support for PNGs; can quantize 32-bit RGBA TIFF images to 8-bit RGBA-palette PNGs.

Version 2.50, Morten Eriksen. Available for Amiga; read-only; requires a PNG datatype such as those from Cloanto or Andreas Kleinert.

Version 3.25, Andreas Kleinert. Available for Amiga 68k/PPC; write-only support for PNGs; supports interlacing and single-color transparency. PNG-Box is a graphical ``any to PNG'' conversion utility that uses Andreas's own SuperView Library for its image support instead of datatypes.

Version 1.14, Tom Tanner. Available for Acorn RISC OS; read-only support for PNGs (converts to Acorn sprite format).

Version of March 10, 1995, Lee Daniel Crocker. Available as portable source code (does not require libpng or zlib); read-only support for PNGs (converts to TIFF); full gamma support (writes TIFF TransferFunction tag); full alpha support for true alpha channels (no palette-alpha or ``cheap transparency'' support).

Version 3.0, Ulead Systems. Available for 32-bit Windows; read/write support for PNGs; full alpha support, including at least single-color palette transparency (not clear whether full RGBA-palette translucency is supported); reportedly cannot write 1-bit (bilevel) images.

Version 0.04b, Darren Salt. Available for Acorn RISC OS; write-only support for PNGs; full alpha support via secondary sprite that is used as a transparency mask or alpha channel; supports interlacing and background color. An older version was reported to produce streaks in conversions of newer (post-RPC) sprites, but this appears to be fixed in the current release.

Version 5.2, Smaller Animals Software. Available for 32-bit Windows; read/write support for PNGs; supports transparency, background color, and text; claims full gamma support.

Version 3.0p1, Felix Schwarz. Available for Amiga 68k/PPC; read/write support for PNGs (natively since version 1.6, or via a datatype for earlier versions); no alpha or gamma support.

New conversion utilities and updated information on the ones listed here can be found at the Image-Conversion Applications with PNG Support web page at the PNG home site, This URL is expected to be stable for years, but of course there are no guarantees on the World Wide Web! Use a search engine to look for the title string or for one of the more oddly named utilities listed if the link should ever break.

Last Update: 2010-Nov-26