Version 4.0, Skyline Tools. This is a 32-bit Windows DLL with Delphi support;
version 2.5 also supported 16-bit Windows. It claims ``support for most PNG
formats'' and ``image conversion,'' which implies that it has read/write
support for PNGs.
- ImageMan ActiveX Suite and ImageMan DLL Suite
Version 6.02, Data Techniques. These are suites of ActiveX controls, Visual
Basic controls, and DLLs for image manipulation and conversion. They support
both 16- and 32-bit Windows and include read/write support for PNGs.
Version 4.3, Smaller Animals Software. This is a 32-bit Windows DLL with
read/write support for PNGs; it claims to support alpha transparency and
gamma correction as well. It can be used with Visual C++, Visual Basic, and so on.
LEAD Technologies. This is a suite of toolkits with image support,
including partial read/write support for PNGs. According to the
features page, 2-bit PNG images and images with 16 bits per sample are
not supported for either reading or writing, and interlacing and alpha
transparency are supported only for reading. LEADTOOLS once supported
DOS and OS/2 platforms in addition to 16- and 32-bit Windows, but now
only Windows appears to be supported.
- PiXCL Tools
Version 4.22, VYSOR Integration. This is an ``interpreted
image-processing and graphics language toolkit'' for creating
multimedia presentations, demos, and imaging applications, especially
for satellite data. It is available for 32-bit Windows, and it
includes both standalone tools and a DLL for user programs.
Version 1.0 beta 5, Peter Beyersdorf. This is an image-manipulation library
for either Delphi 2 or 3 under 32-bit Windows, with read/write support for
PNGs. It includes a simple demo viewer.
Bananas Software. This is an ActiveX control (OCX) for 32-bit Windows. It
includes read/write support for PNGs and a number of other image formats, and
it can be used with Visual C++, Visual Basic, Delphi, in web browsers, and so on.
- Victor Image Processing Library
Version 5.0, Catenary Systems. This is a DLL for 16-bit and 32-bit Windows;
it includes read/write support for PNGs and a number of other image formats,
though PNG is only supported in the 16-bit Windows version with a separate
add-on (freely downloadable). Apparently, only the 32-bit Windows version is
still under active development--the last Windows 3.x release was version 4.25.
There is also a version 3.7 for DOS, but it has no PNG support, and the PNG
add-on does not apply to it.