Convert png64 to fpx

What is the difference between .png64 and .fpx?

Description: A PNG file is an image file stored in the Portable Network Graphic (PNG) format. It contains a bitmap of indexed colors and uses lossless compression, similar to a .GIF file but without copyright limitations. PNG files are commonly used to store graphics for web images.; The FPX (FlashPix Bitmap Image File) format is a type of image file designed to support high-resolution photographs and images. Developed in the mid-1990s by a consortium including Kodak, Microsoft, Hewlett-Packard, and Live Picture Inc., the FPX format is based on the Image Content Architecture (ICA), which allows it to store multiple resolutions of an image within a single file. This makes it especially useful for efficiently viewing and editing images without requiring the full image file.