PNG - Ideas to Integrated Circuits

PNG-supporting Libraries and Toolkits
JIMI is partly based on this.)
● PNG_IO [Steve Sangwine] (many) - all versions; read/write; requires zlib; freeware (GPL) with
source. (This is a basic, high-level Ada 95 package for reading and writing PNG files. It is neither
a clone of nor a wrapper for libpng; for example, versions prior to 3.3 did not support writing
interlaced images, though they could read them. PNG_IO can write gamma, sRGB, and several
other ancillary chunks.)
● Pnglets [Roger E. Critchlow, Jr.] (JavaScript) - all versions; write-only; freeware (GPL) with
source. (This is a PNG drawing library written in JavaScript [not Java!]; it can be used to create
client-side line drawings on the fly, without either libpng or zlib. Pnglets was inspired by and is
partly based on algorithms in the gd library above, but the package draws from other sources as
well and predates gd's PNG support.)
● PNGLIB [Edmund H. Hand, Uberto Barbini, Eric Engler] (Win32) - all versions; read/write;
requires libpng and zlib; freeware with source code. (This is a Delphi wrapper for libpng and
zlib. It appears to have a bug in writing the PNG IEND chunk [failure to include the length field],
though this is strange given its use of libpng.)
● PNGlib [Thomas Kabir] (Win32) - all versions; read-only; full alpha support; freeware with
Visual Basic source. (This is primarily a sample viewer, PNGView, that apparently can
composite a transparent PNG image against a background image; but it also includes complete
source code for a VB PNG-decoding library, PNGlib.)
● PngUnit [Edmund H. Hand, Jack Goman] (Win32) - all versions; read/write; freeware with
source. (This is another Delphi wrapper for libpng and zlib based on Edmund Hand's PngImage.
pas. It apparently includes a viewer with BMP-to-PNG conversion capability.)
● PNGwriter [Paul Blackburn] (any) - all versions; read/write; 16-bit-per-sample support; requires
libpng and zlib; freeware (GPL) with source. (This is a C++ class for plotting XY data and
drawing basic shapes directly to a PNG file. It includes HSV conversion functions,
documentation in both English and Spanish, etc. It's also available from SourceForge.)
● PowerDoc [D-Type] (Win32) - all versions? read/write; commercial. (This is a vector-based
graphics library for creating and rendering "professional, high-quality, and resolutionindependent
documents of any kind." It can import and export PNG images. An ASP variant can
do [web] server-side rendering for IIS Active Server Pages.)
● PrinterCE [FieldSoftware] (Windows CE 3.x) - version 2.0(?) and later; read-only; commercial.
(This is a PNG-supporting printing module for WinCE 3.x, a.k.a. Pocket PC. The toolkit is also
available for older WinCE platforms, but without PNG support.)
http://libpng.org/pub/png/pngaptk.html (16 of 21)10/23/06 12:50 PM