.png
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A PNG image with an 8-bit transparency channel, overlaid onto a checkered background, typically used in graphics software to indicate transparency.
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| Filename extension | .png |
|---|---|
| Internet media type | image/png |
| Type code | PNGf PNG |
| Uniform Type Identifier (UTI) | public.png |
| Magic number | 89 50 4e 47 0d 0a 1a 0a |
| Developed by | PNG Development Group (donated to W3C) |
| Initial release | 1 October 1996 |
| Type of format | lossless bitmap image format |
| Extended to | APNG, JNG and MNG |
| Standard | ISO/IEC 15948,IETF RFC 2083 |
| Open format? | Yes |
Portable Network Graphics (PNG /ˈpɪŋ/) is a raster graphics file format that supports lossless data compression. PNG was created as an improved, non-patented replacement for Graphics Interchange Format (GIF), and is the most widely used lossless image compression format on the Internet.
PNG supports palette-based images (with palettes of 24-bit RGB or 32-bit RGBA colors), grayscale images (with or without alpha channel for transparency), and full-color non-palette-based RGB/RGBA images (with or without alpha channel). PNG was designed for transferring images on the Internet, not for professional-quality print graphics, and therefore does not support non-RGB color spaces such as CMYK. A PNG file contains a single image in an extensible structure of "chunks", encoding the basic pixels and other information such as textual comments and integrity checks.
PNG files nearly always use file extension PNG or png and are assigned MIME media type image/png. PNG was approved for this use by the Internet Engineering Steering Group on 14 October 1996, and was published as an ISO/IEC standard in 2004.
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