Difference between pages "User:Mklauber" and "Portable Network Graphics (PNG)"

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'''Portable Network Graphics''' (aka PNG) is an image file format developed to replace GIF images on the web.  It uses lossless compression and is thus not ideal for photographs. The types of images ideally suited for PNG are line-art, text, other graphics that have sharp transitions.
  
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=Format=
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A PNG file comprises "chunks" of data, some of which are mandatory and others of which are ancillary. Some ancillary chunks can contain metadata text or timestamps, but does not contain nearly as much metadata as [[exif]] images.  All PNG files begin with an 8-byte signature: <tt>89 50 4E 47 0D 0A 1A 0A</tt> (hexadecimaml).
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=See Also=
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* [http://www.forensicswiki.org/wiki/Tools:Document_Metadata_Extraction#Images Tools for extracting image metadata]
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=External Links=
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* [http://en.wikipedia.org/wiki/Portable_Network_Graphics Wikipedia article]
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* [http://www.w3.org/TR/2003/REC-PNG-20031110/ W3C Recommendation]
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[[Category:File Formats]]

Revision as of 09:58, 9 April 2010

Portable Network Graphics (aka PNG) is an image file format developed to replace GIF images on the web. It uses lossless compression and is thus not ideal for photographs. The types of images ideally suited for PNG are line-art, text, other graphics that have sharp transitions.

Format

A PNG file comprises "chunks" of data, some of which are mandatory and others of which are ancillary. Some ancillary chunks can contain metadata text or timestamps, but does not contain nearly as much metadata as exif images. All PNG files begin with an 8-byte signature: 89 50 4E 47 0D 0A 1A 0A (hexadecimaml).

See Also

External Links