This program converts APNG animations into animated GIF format.
Wu64 quantization is used for true-color files. Transparency is handled either
using a threshold, or composed over chosen background color. CLI version is
OS-independent, GUI version is available for Windows. 
Another converter: gif2apng

Features

 * Wu64 quantization for true-color files
 * Flexible options for transparency handling
 * CLI and GUI versions available
 * OS-independent source code is under zlib license