This utility might not be maintained much anymore, if at all.
You might be interested in trying my
Advantages of ImageWorsener over pngrewrite:
- Supports images with more than 256 colors.
- Supports images with 16 bits/sample.
- Has many features other than image optimization.
- More restrictive license.
- Might be even less efficient than pngrewrite.
- Does not maintain as much meta data.
Pngrewrite is command-line utility that reduces the
palettes that some programs write into PNG files. It also optimizes
transparency data, and reduces the bits-per-pixel if possible.
Handy for post-processing PNG files before putting them on a web site.
It can probably run on most any platform on which libpng can run.
A Windows version is included. For other platforms, you'll have to compile
- pngrewrite v1.4.0 - 8 Jun 2010; 140KB
(includes C source code, and a Win32 executable for Windows
Read the included readme.txt file for more details.
- v1.4.0 - 8 Jun 2010
- Lots of code reorganization, cleanup, and routine maintenance.
- For the included pngrewrite.exe file, updated libpng to 1.4.2 and
zlib to 1.2.5.
- v1.3.0 - 7 Dec 2008
- Cleaned up the code somewhat. No more global variables.
- Improved error reporting.
- Disabled "one argument" mode, where the first argument may be taken
as the output file if standard-input is not a terminal. On consideration,
I think there's too much of a risk of overwriting files by accident. It
can be re-enabled at compile time. Otherwise, for piped I/O, use "-" as
the file name.
- Updated libpng in the included pngrewrite.exe file to v1.2.33.
- v1.2.1 - 9 Feb 2003
- Fixed a bug in v1.2.0, which could occasionally
cause the some pixels at the upper left to be the wrong color.
- v1.2.0 - 14 Jun 2002
- v1.1.1 - 11 Jun 2002
- v1.1 - 27 Apr 2002
- v1.0 - 25 Jan 2000