This is a format for editing, storing, and transmitting images with metadata for scientific purposes. The main application is astronomy. The main emphasis is on the metadata, which contain information about spatial and photometric calibrations. FTS is often used for storing data without including the actual associated images. It supports the storage of databases, matrices, etc.
PNG is a raster graphic data storage format that uses lossless compression algorithm to Deflate. PNG was created as a free format to replace GIF. PNG supports three main types of raster images: grayscale image, a color indexed image and the color image. PNG format stores graphical information in a compressed form.