Use FREE & FREEWARE software
Convert GIF to Animated PNG
APNG is a smaller software converting GIF animation to PNG animation (APNG). This program will also make your GIF animations smaller by converting them into Animated PNG format.Gif 2 apng converter is simple to use no installation or anything is required. Just drag and drop a GIF image into the program, it will automatically convert to APNG.
Download: http://sourceforge.net/projects/gif2apng/