TkPNG is an open source binary package that adds PNG photo image support to Tcl/Tk.
Tk does not currently have native support for any image formats that allow for alpha (partial-transparency) channels, although it does have support for alpha blending internally. Using alpha channels for smooth blending and anti-aliasing is a great way to improve the appearance of GUI applications built with Tcl/Tk, especially when combined with Tile.
At this time, the package supports reading images from files or binary data. Base64 decoding is supported as of version 0.6. Exporting images to PNG format is not supported yet.
The TkPNG project supports the full range of color types, channels and bit depths from 1 bit black & white to 16 bit per channel full color with alpha (64 bit RGBA) and interlacing. Ancillary "chunks" such as gamma, color profile, and text fields are ignored, although they are checked at a minimum for correct CRC.
What's New in This Release:
· Moved format alpha value to PNGImage structure. Updated TEA version to 3.6 and regenerated configure script (should fix configure errors under Linux).