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| screenshot = Epepeotes uncinatus @ Kanjirappally Exif 02.png
| caption = Exif of a file in [[Wikimedia Commons]] (compact form)
| extension = <code>.JPG</code>, <code>.TIF</code>, <code>.WAV</code>, <code>.PNG</code>,<ref name="Extensions to the PNG 1.2 Specification, Version 1.5.0">{{cite web |title=Extensions to the PNG 1.2 Specification, Version 1.5.0 |website=ftp-osl.osuosl.org |url=http://ftp-osl.osuosl.org/pub/libpng/documents/pngext-1.5.0.html#C.eXIf |access-date=4 March 2021}}</ref><
| owner = [[Japan Electronic Industries Development Association|JEIDA]], now [[Japan Electronics and Information Technology Industries Association|JEITA]], [[Camera & Imaging Products Association|CIPA]]
| released = {{start date and age|1995}}<ref>{{cite web |url=https://www.loc.gov/preservation/digital/formats/fdd/fdd000146.shtml |title=Exif Exchangeable Image File Format, Version 2.2,Sustainability of Digital Formats: Planning for Library of Congress Collections |website=[[Library of Congress]] |date=26 February 2014 |access-date=2020-08-18}}</ref>
| latest release version =
| latest release date = {{Start date and age|
| extended from = [[
| extended to = [[Design rule for Camera File system|DCF]]
| standard =
}}
'''Exchangeable image file format''' (officially '''Exif''', according to JEIDA/JEITA/CIPA specifications)<ref>{{Cite web |title=Exif2-1.PDF |url=http://www.exif.org/Exif2-1.PDF |url-status=dead |archive-url=https://web.archive.org/web/20131111073619/http://www.exif.org/Exif2-1.PDF |archive-date=2013-11-11 |format=PDF}}</ref> is a standard that specifies [[file format|formats]] for [[image]]s, [[sound]], and ancillary tags used by [[digital camera]]s (including [[smartphone]]s), [[Image scanner|scanners]] and other systems handling image and sound files recorded by digital cameras. The specification uses the following existing encoding formats with the addition of specific [[Metadata (computing)|metadata]] tags: [[JPEG]] lossy coding for compressed image files, [[
This standard consists of the Exif image file specification and the Exif audio file specification.
=={{anchor|1.0|1.1|2.0|R98|2.1|2.2|2.21|2.3|3.0}}Background==
Exif is supported by almost all camera manufacturers.
The metadata tags defined in the Exif standard cover a broad spectrum:
* Camera settings: This includes static information such as the camera model and make, and information that varies with each image such as orientation (rotation), [[aperture]], [[shutter speed]], [[focal length]], [[metering mode]], and [[ISO speed]] information
* Image metrics: Pixel dimensions, resolution, colorspace, and filesize
* Date and time information
* Location information
* A [[thumbnail]] for previewing the picture on the camera's LCD screen, in file managers, or in photo manipulation software
* Descriptions
* Copyright information
==Version history==
{{Expand section|with=changes|date=August 2020}}
The [[Japan Electronic Industries Development Association]] (JEIDA) produced the initial definition of Exif. Version 2.1 of the specification is dated 12
{| class="wikitable"
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|1.0
|October 1995
|Removed dependencies to io package
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|1.1
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|2.0
|November 1997
|License change to MIT license
|-
|2.1
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|2.2
|April 2002
|Added [[High Efficiency Image File Format|HEIC]] support
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|2.21
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|
|-
|3.0
|May 2023
|UTF-8 data type
|}
==Technical==
The Exif tag structure is borrowed from TIFF files. On several image specific properties, there is a large overlap between the tags defined in the [[
When Exif is employed for [[JPEG]] files, the Exif data are stored in one of JPEG's defined utility ''Application Segments'', the APP1 (segment marker 0xFFE1), which in effect holds an entire TIFF file within. When Exif is employed in TIFF files (also when used as "an embedded TIFF file" mentioned earlier), the TIFF Private Tag 0x8769 defines a sub-Image File Directory (IFD) that holds the Exif specified TIFF Tags. In addition, Exif also defines a [[Global Positioning System]] sub-IFD using the TIFF Private Tag 0x8825, holding location information, and an "Interoperability IFD" specified within the Exif sub-IFD, using the Exif tag 0xA005.
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Exif data are embedded within the image file itself. While many recent [[Graphics software|image manipulation programs]] recognize and preserve Exif data when writing to a modified image, this is not the case for most older programs. Many image gallery programs also recognise Exif data and optionally display it alongside the images.
Software libraries, such as libexif<ref>{{cite web | url=https://libexif.github.io/ | title=The libexif C EXIF library | access-date=2022-07-06 }}</ref> for [[C (programming language)|C]] and Adobe XMP Toolkit<ref>{{cite web | url=https://www.adobe.com/devnet/xmp.html | title=Adobe XMP Toolkit SDK | publisher= Adobe Inc. }}</ref> or Exiv2<ref>{{cite web | url=http://www.exiv2.org/ | title=Exiv2 Image Metadata Library | publisher=Andreas Huggel | access-date=2009-02-12 | archive-date=2012-02-12 | archive-url=https://web.archive.org/web/20120212032622/http://www.exiv2.org/ | url-status=dead }}</ref> for [[C++]], Metadata Extractor<ref>{{cite web | url=http://www.drewnoakes.com/code/exif/ | title=Metadata Extractor | publisher=Drew Noakes | access-date=2011-02-18 | archive-date=2007-09-27 | archive-url=https://web.archive.org/web/20070927201245/http://www.drewnoakes.com/code/exif/ | url-status=dead }}</ref> for [[Java (programming language)|Java]], [[Python Imaging Library|PIL/Pillow]] for [[Python (programming language)|Python]], [[LEADTOOLS]] or [[ExifTool]]<ref>{{cite web | url=http://owl.phy.queensu.ca/~phil/exiftool/ | title=Image::ExifTool Perl library | publisher=Phil Harvey | access-date=2009-02-12}}</ref> for [[Perl]], parse Exif data from files and read/write Exif tag values.
==Problems==
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The Exif format has a number of drawbacks, mostly relating to its use of legacy file structures.
* The derivation of Exif from the TIFF file structure using offset pointers in the files means that data can be spread anywhere within a file, which means that software is likely to corrupt any pointers or corresponding data that it
* The standard defines a MakerNote tag, which allows camera manufacturers to place any custom format metadata in the file. This is used increasingly by camera manufacturers to store camera settings not listed in the Exif standard, such as shooting modes, post-processing settings, serial number, focusing modes, etc. As the tag contents are proprietary and manufacturer-specific, it can be difficult to retrieve this information from an image or to properly preserve it when rewriting an image. Manufacturers can encrypt portions of the information; for example, some Nikon cameras encrypt the detailed lens data in the MakerNote data.<ref>{{cite web | title=Nikon Tags: Nikon LensData01 Tags | url=http://owl.phy.queensu.ca/~phil/exiftool/TagNames/Nikon.html#LensData01 | publisher=Phil Harvey | date=2008-01-25 | access-date=2008-01-28}}</ref>
* Exif is very often used in images created by scanners, but the standard makes no provisions for any scanner-specific information.{{citation needed|date=November 2014}}
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Since the Exif tag contains metadata about the photo, it can pose a privacy problem. For example, a photo taken with a [[GPS]]-enabled camera can reveal the exact location and time it was taken, and the unique ID number of the device - this is all done by default - often without the user's knowledge. Many users may be unaware that their photos are tagged by default in this manner, or that specialist software may be required to remove the Exif tag before publishing. For example, a [[whistleblower]], journalist or [[political dissident]] relying on the protection of anonymity to allow them to report [[Misfeasance|malfeasance]] by a corporate entity, criminal, or government may therefore find their safety compromised by this default data collection.
In December 2012, anti-virus businessman [[John McAfee]] was arrested in [[Guatemala]] while fleeing from alleged persecution<ref>{{cite web|url=http://www.cnn.com/2012/12/07/world/americas/guatemala-mcafee-asylum-rejected/index.html |title=McAfee wins stay of deportation from Guatemala |date=7 December 2012 |publisher=
According to documents leaked by [[Edward Snowden]], the [[NSA]] is targeting Exif information under the [[XKeyscore]] program.<ref name =Guardian2>{{cite news| author = Staff | title=XKeyscore Presentation from 2008 – Read in Full – Training Materials for the XKeyscore Program Detail How Analysts Can Use It and Other Systems to Mine Enormous Agency Databases and Develop Intelligence from the Web – Revealed: NSA Program That Collects 'Nearly Everything a User Does on the Internet'|url=https://www.theguardian.com/world/interactive/2013/jul/31/nsa-xkeyscore-program-full-presentation|access-date= August 6, 2013|newspaper= [[The Guardian]] |date= July 31, 2013}}</ref>
The privacy problem of Exif data can be avoided by removing the Exif data using a [[metadata removal tool]].<ref>Hassan, Nihad, and Hijazi, Rami. [https://books.google.com/books?id=U-AqDwAAQBAJ
==Related standards==
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===Example===
[[File:DigiKam EXIF information screenshot.png|thumb|right|[[DigiKam]] screenshot showing Exif data]]
The following table shows Exif metadata for a photo made with a typical digital camera.
{| class="wikitable" style="margin:auto;"
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|-
|Orientation (rotation)
|top-left [8 possible values<ref>{{cite web |url=
|-
|Software
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==See also==
* [[APEX system]]
* [[Comparison of image viewers]] (Exif view/edit functions)
* [[Design rule for Camera File system]] (DCF)
* [[Digital photography]]
* [[eXtensible Metadata Platform]] (XMP)
* [[
* [[Image file
* [[IPTC Information Interchange Model]]
* [[JPEG File Interchange Format]]
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* [https://cipa.jp/e/std/std-sec.html CIPA Standards - Camera & Imaging Products Association]
* [https://www.cipa.jp/std/documents/download_e.html?DC-008-Translation-2023-E Exif standard version 3.0]
* [https://www.cipa.jp/std/documents/e/DC-X008-Translation-2019-E.pdf Exif standard version 2.32 *New]
* [http://www.cipa.jp/std/documents/e/DC-008-2012_E.pdf Exif standard version 2.3]
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