Difference between pages "Nokia" and "GIF"

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Nokia Corporation is a Finnish multinational communications corporation, headquartered in Keilaniemi, Espoo, a city neighbouring Finland's capital Helsinki. Nokia is focused on wireless and wired telecommunications, with 112,262 employees in 120 countries, sales in more than 150 countries and global annual revenue of 51.1 billion euros and operating profit of 8.0 billion as of 2007. It is the world's largest manufacturer of mobile telephones: its global device market share was about 40% in Q2 of 2008, up from 38% in Q2 2007 and up from 39% sequentially. Nokia produces mobile phones for every major market segment and protocol, including GSM, CDMA, and W-CDMA (UMTS). Nokia's subsidiary Nokia Siemens Networks produces telecommunications network equipments, solutions and services.
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The '''Graphics Interchange Format''' ('''GIF''') (SM) format is a lossless [[image format]]. GIF images use internal [[LZW]] compression to reduce file size. CompuServe created this format, which is a bitmap image format allowing 256 different colors to be selected from a 24-bit color palette (RGB). GIF also allows for animations by sequencing through multiple GIF image data inside a single file.
  
==Nokia Tools==
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"The Graphics Interchange Format(c) is the Copyright property of CompuServe Incorporated. GIF(sm) is a Service Mark property of CompuServe Incorporated."
THC has developed the [http://thc.org.segfault.net/thc-nokia-unlock/ THC NOKIA PHONE-LOCK RESET] which unlocks a locked Nokia phone that has a MMC slot. The unlock is a small program that the phone automatically loads and runs from the MMC slot when the phone boots.
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==External links==
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== Format ==
*[http://www.nokia.com/ Official Nokia portal]
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*[http://www.gsmsolutionsltd.com/download/Nokia_Product_History.pdf Complete Nokia Product History (PDF 179kb)]
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*[http://biz.yahoo.com/ic/41/41820.html Yahoo! – Nokia Corporation Company Profile]
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*[http://www.cogmap.com/chart/nokia Nokia Organization Chart]
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*[http://www.symbianfreeware.org/ Symbian Freeware for Nokia]
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[[Category:Vendor]]
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GIF files consist of a [[header]], image data, optional [[metadata]], and a [[footer]]. The header consists of a signature and a version, each 3 bytes long.  The signature is <tt>47 49 46</tt> (hex) / <tt>GIF</tt> (text).  The versions are either <tt>38 37 61</tt> or <tt>38 39 61</tt> (hex) / <tt>87a</tt> or <tt>89a</tt> (text) respectively.  The footer or trailer (as identified in the format specification) is usually <tt>3B</tt> (hex).
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Common file extensions are .gif and .GIF
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== Metadata ==
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GIF89a files can contain [[metadata]] in [[text]] format.  GIF metadata is contained in sections identified as a Comment Extension, a Plain Text Extension, and an Application Extension.  All extension sections begin with the Extension Introducer <tt>21</tt> (hex).
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Comment Extensions are optional and more than one may be present.  They were designed to allow including comments about the graphic, credits, descriptions or other types of non-control/non-graphic data.  The beginning of this block has the Extension Introducer and a Comment Label <tt>FE</tt> (hex).  Comment data has a sequence of sub-blocks between 1 and 255 bytes in length, with the size in a byte before the data.  Comment Extensions should appear either before or after the control and graphic data blocks.
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Plain Text Extensions are optional and more than one may be present.  They were designed to allow rendering of textual data as a graphic.  The beginning of this block has the Extension Introducer and a Comment Label <tt>01</tt> (hex).  Plain text data has a sequence of sub-blocks between 1 and 255 bytes in length, with the size in a byte before the data.
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Application Extensions are optional. They were designed to allow applications to insert application specific data inside a GIF. The beginning of this block has the Extension Introducer and an Application Extension Label <tt>FF</tt> (hex). 
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== External Links ==
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* [http://en.wikipedia.org/wiki/GIF Wikipedia: GIF]
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* [http://www.w3.org/Graphics/GIF/spec-gif89a.txt W3.Org: GRAPHICS INTERCHANGE FORMAT SPECIFICATION]
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[[Category:File Formats]]

Revision as of 16:43, 23 January 2007

The Graphics Interchange Format (GIF) (SM) format is a lossless image format. GIF images use internal LZW compression to reduce file size. CompuServe created this format, which is a bitmap image format allowing 256 different colors to be selected from a 24-bit color palette (RGB). GIF also allows for animations by sequencing through multiple GIF image data inside a single file.

"The Graphics Interchange Format(c) is the Copyright property of CompuServe Incorporated. GIF(sm) is a Service Mark property of CompuServe Incorporated."

Format

GIF files consist of a header, image data, optional metadata, and a footer. The header consists of a signature and a version, each 3 bytes long. The signature is 47 49 46 (hex) / GIF (text). The versions are either 38 37 61 or 38 39 61 (hex) / 87a or 89a (text) respectively. The footer or trailer (as identified in the format specification) is usually 3B (hex).

Common file extensions are .gif and .GIF

Metadata

GIF89a files can contain metadata in text format. GIF metadata is contained in sections identified as a Comment Extension, a Plain Text Extension, and an Application Extension. All extension sections begin with the Extension Introducer 21 (hex).

Comment Extensions are optional and more than one may be present. They were designed to allow including comments about the graphic, credits, descriptions or other types of non-control/non-graphic data. The beginning of this block has the Extension Introducer and a Comment Label FE (hex). Comment data has a sequence of sub-blocks between 1 and 255 bytes in length, with the size in a byte before the data. Comment Extensions should appear either before or after the control and graphic data blocks.

Plain Text Extensions are optional and more than one may be present. They were designed to allow rendering of textual data as a graphic. The beginning of this block has the Extension Introducer and a Comment Label 01 (hex). Plain text data has a sequence of sub-blocks between 1 and 255 bytes in length, with the size in a byte before the data.

Application Extensions are optional. They were designed to allow applications to insert application specific data inside a GIF. The beginning of this block has the Extension Introducer and an Application Extension Label FF (hex).

External Links