Definition(en): Portable Network Graphics (PNG) was designed for the lossless, portable, compressed storage of raster images. PNG provides a patent-free replacement for GIF and can also replace many common uses of TIFF. Indexed-color, grayscale, and truecolor images are supported, plus an optional alpha channel. Sample depths range from 1 to 16 bits. PNG is designed to work in online viewing applications, so it is fully streamable. It can store gamma and chromaticity. PNG also detects file corruption.