Difference between revisions of "JPEG"

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'''JPEG files''' consist of a well defined header, some [[metadata]], and a well defined footer.
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The '''Joint Photographic Experts Group''' ('''JPEG''') format is a commonly-used lossy [[image format]].
  
The header is usually, in hex <tt>FFd8</tt>.
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= Format =
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JPEG is a container file format that consist of a well defined [[header]], some [[metadata]], icons, a color table, compressed data, and a well defined [[footer]]. The header is usually <tt>FF D8</tt> (hex).
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Common file extensions are .jpg, .jpeg, .JPG, .JPE, and .jfif.
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= Metadata =
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JPEG files can contain lots of [[metadata]] in several formats: [[Exif]], [[IPTC]], GPS, [[Camera Raw]], etc.
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The [[exif]] and [[jhead]] command tools can extract and manipulate some of that metadata. [[Adroit Photo Forensics]] can
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be used to extract, view and group metadata from jpeg and camera Raw files.  In iOS, the [[Photo Investigator]] can extract, view, and remove metadata from all images.
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= Externals Links =
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* [http://en.wikipedia.org/wiki/JPEG Wikipedia: JPEG]
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* [http://www.w3.org/Graphics/JPEG/itu-t81.pdf ISO/IEC 10918-1], Section: Annex B contains a detailed description of the JPEG file structure.
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* [http://www.w3.org/Graphics/JPEG/jfif3.pdf JPEG File Interchange Format Version 1.02]
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* [http://www.exif.org/specifications.html EXIF Specifications]
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* [http://www.exif.org/Exif2-2.PDF Exchangeable image file format for digital still cameras: Exif Version 2.2]
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* [http://www.adobe.com/products/xmp/related.html Extensible Metadata Platform (XMP)]
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* [http://partners.adobe.com/public/developer/en/xmp/sdk/XMPspecification.pdf Adobe - XMP Specification]
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[[Category:File Formats]]

Revision as of 13:20, 9 October 2013

The Joint Photographic Experts Group (JPEG) format is a commonly-used lossy image format.


Format

JPEG is a container file format that consist of a well defined header, some metadata, icons, a color table, compressed data, and a well defined footer. The header is usually FF D8 (hex).

Common file extensions are .jpg, .jpeg, .JPG, .JPE, and .jfif.

Metadata

JPEG files can contain lots of metadata in several formats: Exif, IPTC, GPS, Camera Raw, etc. The exif and jhead command tools can extract and manipulate some of that metadata. Adroit Photo Forensics can be used to extract, view and group metadata from jpeg and camera Raw files. In iOS, the Photo Investigator can extract, view, and remove metadata from all images.

Externals Links