View source for TIFF

{{short description|Series of image file formats}}
{{redirect|TIF|other uses|TIF (disambiguation)|and|TIFF (disambiguation)}}
{{More citations needed|date=October 2023}}
{{Infobox file format
| name          = TIFF
| icon          = TIFF wordmark logo.svg
| iconcaption   = Wordmark of the ''TIFF Revision 6.0''
| icon_size     = 100px
| screenshot    = 
| screenshot_size = 
| caption =
| _noextcode    = on
| extensions    = {{code|.tiff}}, {{code|.tif}}
| _nomimecode   = on
| mime          = {{plainlist|
* {{code|image/tiff}}
* {{code|image/tiff-fx}}
}}
| type code     = TIFF
| uniform type  = public.tiff
| magic         = 49 49 2A 00 or 4D 4D 00 2A
| owner         = [[Aldus Corporation]], now [[Adobe Inc.]]
| released      = {{start date and age|September 12, 1986}}
| latest release version = TIFF 6.0
| latest release date = {{Start date and age|1992|06|03|df=yes}}<br />TIFF Supplement 2 / {{Start date and age|2002|03|22|df=yes}}
| genre         = [[Image file formats|Image file format]]
| container for = 
| contained by  = 
| extended from = tiff
| extended to   = [[Exchangeable image file format|Exif]], [[Design rule for Camera File system|DCF]], [[Tag Image File Format / Electronic Photography|TIFF/EP]], TIFF/IT, TIFF-FX, [[GeoTIFF]]
| standard      = 
| url           = {{url|https://www.loc.gov/preservation/digital/formats/fdd/fdd000022.shtml}}
}}

'''Tag Image File Format'''<ref>{{cite web |url=https://www.adobe.com/creativecloud/file-types/image/raster/tiff-file.html |title=What are TIFF files and how do you open them? |author=<!--Not stated--> |date=<!--Not stated--> |website=adobe.com |publisher=Adobe, Inc. |access-date=November 3, 2023 |quote=A TIFF, which stands for Tag Image File Format, is a computer file used to store raster graphics and image information.}}</ref> or '''Tagged Image File Format''',<ref>{{cite web |url=https://www.adobe.com/creativecloud/file-types/image/comparison/tiff-vs-png.html |title=PNG vs. TIFF: Which is better? |author=<!--Not stated--> |date=<!--Not stated--> |website=adobe.com |publisher=Adobe, Inc. |access-date=November 4, 2023 |quote=TIFF (Tagged Image File Format) files are common in publishing, photo editing, and graphic design.}}</ref> commonly known by the abbreviations '''TIFF''' or '''TIF''', is an [[image file format]] for storing [[raster graphics]] images, popular among graphic artists, the publishing industry,<ref name="sgi">{{cite book |title=Encyclopedia of Graphics File Formats |edition=Second |date=April 1996 |first1=James D. |last1=Murray |first2=William |last2=vanRyper |isbn=1-56592-161-5 |publisher=[[O'Reilly Media|O'Reilly]] |url=https://archive.org/details/mac_Graphics_File_Formats_Second_Edition_1996 |access-date=2014-03-07 |url-access=registration }}</ref> and photographers. TIFF is widely supported by [[image scanner|scanning]], [[FAX|faxing]], [[word processor|word processing]], [[optical character recognition]], image manipulation, [[desktop publishing]], and page-layout applications.<ref>TIFF was chosen as the native format for raster graphics in the [[NeXTstep]] operating system; this TIFF support carried over into [[Mac OS X]].</ref> The format was created by the [[Aldus Corporation]] for use in desktop publishing. It published the latest version 6.0 in 1992, subsequently updated with an [[Adobe Systems]] copyright after the latter acquired Aldus in 1994. Several Aldus or Adobe technical notes have been published with minor extensions to the format, and several specifications have been based on TIFF 6.0, including [[Tag Image File Format / Electronic Photography|TIFF/EP]] (ISO 12234-2), TIFF/IT (ISO 12639),<ref name="TIFF/IT">{{cite web
|title=TIFF/IT ISO/IEC 12639
|publisher=ISO
|year=1998
|url=http://www.iso.org/iso/iso_catalogue/catalogue_ics/catalogue_detail_ics.htm?csnumber=2181
}}</ref><ref name="TIFF/IT2">{{cite web
|title=TIFF/IT for Image Technology
|publisher=The National Digital Information Infrastructure and Preservation Program at the Library of Congress
|date=2006-10-03
|url=http://www.digitalpreservation.gov/formats/fdd/fdd000072.shtml
}}</ref><ref name="prepressure-tiffit">{{cite web |url=http://www.prepressure.com/library/file-formats/tiffit |title=The TIFF/IT file format |access-date=2011-02-19}}</ref> TIFF-F (RFC 2306) and TIFF-FX (RFC 3949).<ref>{{cite web |url=https://tools.ietf.org/html/rfc3949 |title=File Format for Internet Fax |year=2005 |quote=This file format specification is commonly known as TIFF for Fax eXtended (TIFF-FX). |access-date=2011-02-19}}</ref>

==History==
TIFF was created as an attempt to get desktop [[Image scanner|scanner]] vendors of the mid-1980s to agree on a common scanned image file format, in place of a multitude of [[proprietary format]]s. In the beginning, TIFF was only a [[binary image]] format (only two possible values for each pixel), because that was all that desktop scanners could handle. As scanners became more powerful, and as desktop computer disk space became more plentiful, TIFF grew to accommodate [[grayscale]] images, then color images. Today, TIFF, along with [[JPEG]] and [[PNG]], is a popular format for [[Deep color|deep-color]] images.

The first version of the TIFF specification was published by the [[Aldus Corporation]] in the autumn of 1986 after two major earlier draft releases. It can be labeled as Revision 3.0. It was published after a series of meetings with various scanner manufacturers and software developers. In April 1987 Revision 4.0 was released and it contained mostly minor enhancements. In October 1988 Revision 5.0 was released and it added support for palette color images and [[Lempel–Ziv–Welch|LZW compression]].<ref name="tiff6">[https://www.itu.int/itudoc/itu-t/com16/tiff-fx/docs/tiff6.pdf TIFF Revision 6.0 Final — June 3, 1992], Retrieved on 2024-03-29</ref>

TIFF is a complex format, defining many tags of which typically only a few are used in each file. This led to implementations supporting many varying subsets of the format, a situation that gave rise to the joke that TIFF stands for ''Thousands of Incompatible File Formats''.<ref name="trauth">{{cite book
|title=MATLAB Recipes For Earth Sciences
|last=Trauth
|first=Martin H.
|publisher=Springer
|year=2006
|isbn=3-540-27983-0
|page=198
}}</ref> This problem was addressed in revision 6.0<ref name="tiff6" /> of the TIFF specification (June 1992) by introducing a distinction between ''Baseline TIFF'' (which all implementations were required to support) and ''TIFF Extensions'' (which are optional). Additional extensions are defined in two supplements to the specification which were published in September 1995<ref name="supplement1"/> and March 2002<ref name="supplement2">[https://web.archive.org/web/20120111100404/http://partners.adobe.com/public/developer/en/tiff/TIFFphotoshop.pdf TIFF Specification Supplement 2], Retrieved 2022-06-29</ref> respectively.

== Overview ==
A TIFF file contains one ''or several'' images, termed ''subfiles'' in the specification. The basic use case for having multiple subfiles is to encode a multipage [[telefax]] in a single file, but it is also allowed to have different subfiles be different variants of the same image, for example scanned at different resolutions. Rather than being a continuous range of bytes in the file, each subfile is a data structure whose top-level entity is called an ''image file directory'' (IFD). Baseline TIFF readers are only required to make use of the first subfile, but each IFD has a field for linking to a next IFD.

The IFDs are where the ''tags'' for which TIFF is named are located. Each IFD contains one or several ''entries'', each of which is identified by its tag. The tags are arbitrary 16-bit numbers; their symbolic names such as ImageWidth often used in discussions of TIFF data do not appear explicitly in the file itself. Each IFD entry has an associated ''value'', which may be decoded based on general rules of the format, but it depends on the tag what that value then ''means''. There may within a single IFD be no more than one entry with any particular tag. Some tags are for linking to the actual image data, other tags specify how the image data should be interpreted, and still other tags are used for image [[metadata]].

TIFF images are made up of rectangular<ref>Nothing prevents someone defining a TIFF extension that would introduce some other kind of pixel geometry, or even house non-pixel-based graphics in a TIFF container, but so far there does not seem to have been any need for that. Hence TIFF images have a rectangular pixel geometry.</ref> grids of pixels. The two axes of this geometry are termed horizontal (or X, or width) and vertical (or Y, or length). Horizontal and vertical [[image resolution|resolution]] need not be equal (since in a telefax they typically would not be equal). A baseline TIFF image divides the vertical range of the image into one or several ''strips'', which are encoded (in particular: compressed) separately. Historically this served to facilitate TIFF readers (such as fax machines) with limited capacity to store uncompressed data — one strip would be decoded and then immediately printed — but the present specification motivates it by "increased editing flexibility and efficient I/O buffering".<ref name="tiff6" />{{rp|19}} A TIFF extension provides the alternative of ''tiled'' images, in which case both the horizontal and the vertical ranges of the image are decomposed into smaller units.

An example of these things, which also serves to give a flavor of how tags are used in the TIFF encoding of images, is that a striped TIFF image would use tags 273&nbsp;(StripOffsets), 278&nbsp;(RowsPerStrip), and 279&nbsp;(StripByteCounts). The StripOffsets point to the blocks of image data, the StripByteCounts say how long each of these blocks are (as stored in the file), and RowsPerStrip says how many rows of pixels there are in a strip; the latter is required even in the case of having just one strip, in which case it merely duplicates the value of tag 257&nbsp;(ImageLength). A tiled TIFF image instead uses tags 322&nbsp;(TileWidth), 323&nbsp;(TileLength), 324&nbsp;(TileOffsets), and 325&nbsp;(TileByteCounts). The pixels within each strip or tile appear in [[Row- and column-major order|row-major]] order, left to right and top to bottom.

The data for one pixel is made up of one or several ''samples''; for example an [[RGB color model|RGB]] image would have one Red sample, one Green sample, and one Blue sample per pixel, whereas a greyscale or palette color image only has one sample per pixel. TIFF allows for both [[additive color|additive]] (e.g. RGB, [[RGBA]]) and [[subtractive color|subtractive]] (e.g. [[CMYK color model|CMYK]]) color models. TIFF does not constrain the number of samples per pixel (except that there must be enough samples for the chosen color model), nor does it constrain how many bits are encoded for each sample, but baseline TIFF only requires that readers support a few combinations of color model and bit-depth of images. Support for custom sets of samples is very useful for scientific applications; 3 samples per pixel is at the low end of [[multispectral image|multispectral imaging]], and [[hyperspectral imaging]] may require hundreds of samples per pixel. TIFF supports having all samples for a pixel next to each other within a single strip/tile (PlanarConfiguration = 1) but also different samples in different strips/tiles (PlanarConfiguration = 2). The default format for a sample value is as an unsigned integer, but a TIFF extension allows declaring them as alternatively being signed integers or [[IEEE-754]] floats, as well as specify a custom range for valid sample values.

TIFF images may be uncompressed, compressed using a [[lossless compression]] scheme, or compressed using a [[lossy compression]] scheme. The lossless [[LZW]] compression scheme has at times been regarded as the standard compression for TIFF, but this is technically a TIFF extension, and the TIFF6 specification notes the patent situation regarding LZW. Compression schemes vary significantly in at what level they process the data: LZW acts on the stream of bytes encoding a strip or tile (without regard to sample structure, bit depth, or row width), whereas the JPEG compression scheme both transforms the sample structure of pixels (switching to a different color model) and encodes pixels in 8×8 blocks rather than row by row.

Most data in TIFF files are numerical, but the format supports declaring data as rather being textual, if appropriate for a particular tag. Tags that take textual values include Artist, Copyright, DateTime, DocumentName, InkNames, and Model.

===MIME type===
The MIME type ''image/tiff'' (defined in RFC 3302) without an application parameter is used for Baseline TIFF 6.0 files or to indicate that it is not necessary to identify a specific subset of TIFF or TIFF extensions. The optional "application" parameter (Example: Content-type: image/tiff; application=foo) is defined for image/tiff to identify a particular subset of TIFF and TIFF extensions for the encoded image data, if it is known. According to RFC 3302, specific TIFF subsets or TIFF extensions used in the application parameter must be published as an RFC.<ref name="jdf" />

[[MIME]] type ''image/tiff-fx'' (defined in RFC 3949 and RFC 3950) is based on TIFF 6.0 with TIFF Technical Notes TTN1 (Trees) and TTN2 (Replacement TIFF/JPEG specification). It is used for [[Internet fax]] compatible with the ITU-T Recommendations for Group 3 black-and-white, grayscale and color [[fax]].

=== Digital preservation ===
Adobe holds the copyright on the TIFF specification (aka TIFF 6.0) along with the two supplements that have been published.  These documents can be found on the Adobe TIFF Resources page.<ref>{{cite web |url=https://www.adobe.io/open/standards/TIFF.html |title=Adobe TIFF Resources page |access-date=2022-06-29  |archive-url=https://web.archive.org/web/20210108172855/https://www.adobe.io/open/standards/TIFF.html |archive-date=8 January 2021 |url-status=dead}}</ref> The [[Fax]] standard in RFC 3949 is based on these TIFF specifications.<ref name="LoC">{{cite web|url=http://www.digitalpreservation.gov/formats/fdd/fdd000022.shtml|title=TIFF, Revision 6.0|publisher=[[Library of Congress]]|work=Digital Preservation|date=2014-01-08|access-date=2014-03-11}}</ref>

TIFF files that strictly use the basic "tag sets" as defined in TIFF 6.0 along with restricting the compression technology to the methods identified in TIFF 6.0 and are adequately tested and verified by multiple sources for all documents being created can be used for storing documents.   Commonly seen issues encountered in the content and [[document management]] industry associated with the use of TIFF files arise when the structures contain proprietary headers, are not properly documented, or contain "wrappers" or other containers around the TIFF datasets, or include improper compression technologies, or those compression technologies are not properly implemented.

Variants of TIFF can be used within [[document imaging]] and content/document management systems using [[ITU-T|CCITT]] [[Group 4 compression|Group IV 2D compression]] which supports [[black-and-white]] (bitonal, [[monochrome]]) images, among other compression technologies that support [[color]]. When storage capacity and network bandwidth was a greater issue than commonly seen in today's server environments, high-volume storage scanning, documents were scanned in black and white (not in color or in grayscale) to conserve storage capacity.

The inclusion of the SampleFormat tag in TIFF 6.0 allows TIFF files to handle advanced pixel data types, including integer images with more than 8 bits per channel and floating point images. This tag made TIFF 6.0 a viable format for scientific image processing where extended precision is required. An example would be the use of TIFF to store images acquired using scientific CCD cameras that provide up to 16 bits per [[photosite]] of intensity resolution. Storing a sequence of images in a single TIFF file is also possible, and is allowed under TIFF 6.0, provided the rules for multi-page images are followed.{{Citation needed|date=July 2024}}

== Details ==
TIFF is a flexible, adaptable file format for handling images and data within a single file, by including the header tags (size, definition, image-data arrangement, applied [[image compression]]) defining the image's geometry. A TIFF file, for example, can be a container holding [[JPEG]] (lossy) and [[PackBits]] (lossless) compressed images. A TIFF file also can include a [[Vector graphics|vector]]-based [[clipping path]] (outlines, croppings, image frames). The ability to store image data in a [[Lossless data compression|lossless]] format makes a TIFF file a useful image archive, because, unlike standard JPEG files, a TIFF file using lossless compression (or none) may be edited and re-saved without losing image quality. This is not the case when using the TIFF as a container holding compressed JPEG. Other TIFF options are [[Layers (digital image editing)|layers]] and pages.

TIFF offers the option of using [[Lempel-Ziv-Welch|LZW]] compression, a lossless data-compression technique for reducing a file's size. Use of this option was limited by patents on the LZW technique until their expiration in 2004.

The TIFF 6.0 specification consists of the following parts:<ref name="tiff6" />
* Introduction (contains information about TIFF Administration, usage of Private fields and values, etc.)
* Part 1: Baseline TIFF
* Part 2: TIFF Extensions
* Part 3: Appendices

=== {{anchor|Baseline TIFF}}Part 1: Baseline TIFF ===
When TIFF was introduced, its extensibility provoked compatibility problems. The flexibility in encoding gave rise to the joke that TIFF stands for ''Thousands of Incompatible File Formats''.<ref name="trauth"/> To avoid these problems, every TIFF reader was required to read ''Baseline TIFF''. Among other things, Baseline TIFF does not include layers, or compressed JPEG or LZW images. Baseline TIFF is formally known as ''TIFF 6.0, Part 1: Baseline TIFF''.

The following is an incomplete list of required Baseline TIFF features:<ref name="tiff6" />

==== Multiple subfiles ====
TIFF readers must be prepared for multiple/multi-page images (subfiles) per TIFF file, although they are not required to actually do anything with images after the first one.

There may be more than one Image File Directory (IFD) in a TIFF file. Each IFD defines a subfile. One use of subfiles is to describe related images, such as the pages of a facsimile document. A Baseline TIFF reader is not required to read any IFD beyond the first one.<ref name="tiff6" />

==== Strips ====
A baseline TIFF image is composed of one or more strips. A strip (or band) is a subsection of the image composed of one or more rows. Each strip may be compressed independently of the entire image, and each begins on a byte boundary. If the image height is not evenly divisible by the number of rows in the strip, the last strip may contain fewer rows. If strip definition tags are omitted, the image is assumed to contain a single strip.

==== Compression ====
Baseline TIFF readers must handle the following three compression schemes:<ref name="tiff6" />
* Zero compression
* [[ITU-T|CCITT]] Group 3 1-Dimensional Modified [[Huffman coding|Huffman]] RLE
* [[PackBits]] compression - a form of [[run-length encoding]]

==== Image types ====
Baseline TIFF image types are: bilevel, grayscale, palette-color, and RGB full-color images.<ref name="tiff6" />

==== Byte order ====
Every TIFF file begins with a two-[[byte]] indicator of [[byte order]]: "<code>II</code>" for little-endian (a.k.a. "Intel byte ordering", {{circa|1980}})<ref name="ReferenceA">David Beecher, author of dozens of image processing engines over the last 30 years. Any TIFF file can be viewed with a HEX editor to confirm this.</ref> or "<code>MM</code>" for big-endian (a.k.a. "Motorola byte ordering", {{circa|1980}})<ref name="ReferenceA"/> byte ordering. The next two-byte word contains the format version number, which has always been 42 for every version of TIFF (e.g., TIFF v5.0 and TIFF v6.0).<ref>{{cite book
 |     author = Aldus/Microsoft
 |      title = TIFF
 |    section = 1) Structure
 |    version = Revision 5.0
 |  publisher = Aldus Corporation and Microsoft Corporation
 |       date = 1988-08-08
 |        url = http://cool-palimpsest.stanford.edu/bytopic/imaging/std/tiff5.html
 | archive-url = https://web.archive.org/web/20081204070129/http://cool-palimpsest.stanford.edu/bytopic/imaging/std/tiff5.html
 |archive-date = 2008-12-04
 | access-date = 2009-06-29
 |      quote = The number 42 was chosen for its deep philosophical significance.
 }}</ref>
All two-byte words, double words, etc., in the TIFF file are assumed to be in the indicated byte order. The TIFF 6.0 specification states that compliant TIFF readers must support both byte orders (<code>II</code> and <code>MM</code>); writers may use either.<ref>{{cite book
 |author      = Adobe Developers Association
 |title       = TIFF
 |section     = Section 7: Additional baseline TIFF Requirements
 |version     = Revision 6.0
 |publisher   = Adobe Systems Incorporated
 |date        = 1992-06-03
 |url         = https://www.adobe.io/content/dam/udp/en/open/standards/tiff/TIFF6.pdf
 |access-date  = 2022-06-29
 |quote       = ‘MM’ and ‘II’ byte order. TIFF readers must be able to handle both byte orders. TIFF writers can do whichever is most convenient or efficient.
 |page        = 26
 |archive-url=https://web.archive.org/web/20210108174645/https://www.adobe.io/content/dam/udp/en/open/standards/tiff/TIFF6.pdf
 |archive-date=8 January 2021 |url-status=dead}}</ref>

==== Other TIFF fields ====
TIFF readers must be prepared to encounter and ignore private fields not described in the TIFF specification. TIFF readers must not refuse to read a TIFF file if optional fields do not exist.<ref name="tiff6" />

=== {{anchor|TIFF Extensions}}Part 2: TIFF Extensions ===
Many TIFF readers support tags additional to those in Baseline TIFF, but not every reader supports every extension.<ref>{{cite web |url=http://support.microsoft.com/kb/319196/en-us |title=You cannot preview scanned TIFF file in Windows Picture and Fax Viewer |author=Microsoft |access-date=2011-02-28}}</ref><ref name="wfax-packbits">{{cite web |url=http://support.microsoft.com/kb/329270 |title=You Cannot View TIFF Images Using Windows Picture and Fax Viewer |author=Microsoft |access-date=2011-02-28}}</ref><ref>{{cite web |url=http://suppressingfire.org/~burner/evil-mods-tiff/ |title=Handling Microsoft Office Document Scanning TNEF and TIFFs in Linux |author=Microsoft |access-date=2011-02-28 |url-status=dead |archive-url=https://web.archive.org/web/20130430204808/http://suppressingfire.org/~burner/evil-mods-tiff/ |archive-date=2013-04-30 }}</ref> As a consequence, Baseline TIFF features became the lowest common denominator for TIFF. Baseline TIFF features are extended in TIFF Extensions (defined in the TIFF 6.0 Part 2 specification) but extensions can also be defined in private tags.

The TIFF Extensions are formally known as ''TIFF 6.0, Part 2: TIFF Extensions''. Here are some examples of TIFF extensions defined in TIFF 6.0 specification:<ref name="tiff6" />

====Compression====
* CCITT T.4 bi-level encoding
* CCITT T.6 bi-level encoding
* [[Lempel–Ziv–Welch|LZW]]
* [[JPEG]]

====Image types====
* [[CMYK]] Images
* [[YCbCr]] Images
* HalftoneHints
* Tiled Images
* [[CIE Lab|CIE L*a*b*]] Images

====Image trees====
A baseline TIFF file can contain a sequence of images (IFD). Typically, all the images are related but represent different data, such as the pages of a document. In order to explicitly support multiple views of the ''same'' data, the ''SubIFD'' tag was introduced.<ref name="supplement1">[https://web.archive.org/web/20060114005938/http://partners.adobe.com/public/developer/en/tiff/TIFFPM6.pdf TIFF Specification Supplement 1], Retrieved 2022-06-29</ref> This allows the images to be defined along a [[tree structure]]. Each image can have a sequence of children, each child being itself an image. The typical usage is to provide thumbnails or several versions of an image in different color spaces.

=====Tiles=====
A TIFF image may also be composed of a number of tiles. All tiles in the same image have the same dimensions and may be compressed independently of the entire image, similar to strips (see above). Tiled images are part of TIFF 6.0, Part 2: TIFF Extensions, so the support for tiled images is not required in Baseline TIFF readers.

====Other extensions====
According to TIFF 6.0 specification (Introduction), all TIFF files using proposed TIFF extensions that are not approved by Adobe as part of Baseline TIFF (typically for specialized uses of TIFF that do not fall within the domain of publishing or general graphics or picture interchange) should be either not called TIFF files or should be marked some way so that they will not be confused with mainstream TIFF files.

==== Private tags ====
Developers can apply for a block of "private tags" to enable them to include their own proprietary information inside a TIFF file without causing problems for file interchange. TIFF readers are required to ignore tags that they do not recognize, and a registered developer's private tags are guaranteed not to clash with anyone else's tags or with the standard set of tags defined in the specification. Private tags are numbered in the range 32,768 and higher.

Private tags are reserved for information meaningful only for some organization, or for experiments with a new compression scheme within TIFF. Upon request, the TIFF administrator (currently Adobe) will allocate and register one or more private tags for an organization, to avoid possible conflicts with other organizations. Organizations and developers are discouraged from choosing their own tag numbers arbitrarily, because doing so could cause serious compatibility problems. However, if there is little or no chance that TIFF files will escape a private environment, organizations and developers are encouraged to consider using TIFF tags in the "reusable" 65,000–65,535 range. There is no need to contact Adobe when using numbers in this range.<ref name="tiff6" />

===TIFF Compression Tag===
The TIFF Tag 259 (0103<sub>16</sub>) stores the information about the Compression method. The default value is 1 = no compression.

Most TIFF writers and TIFF readers support only some TIFF compression schemes. Here are some examples of used TIFF compression schemes:
{|class="wikitable sortable" style="width: 100%"
|+ TIFF Compression Tag<ref name="wfax-packbits" /><ref>{{cite web |url=http://www.awaresystems.be/imaging/tiff/tifftags/compression.html |title=Baseline TIFF Tag Compression |access-date=2011-02-26}}</ref><ref>{{cite web |url=http://www.libtiff.org/support.html |title=LibTIFF - TIFF 6.0 Specification Coverage |access-date=2011-02-28}}</ref><ref>{{cite web|url=http://hul.harvard.edu/jhove/tiff-tags.html |title=JSTOR/Harvard Object Validation Environment - TIFF Compression Schemes |access-date=2011-02-26 |url-status=dead |archive-url=https://web.archive.org/web/20110130161333/http://hul.harvard.edu/jhove/tiff-tags.html |archive-date=January 30, 2011 }}</ref><ref>{{cite web|url=http://hul.harvard.edu/jhove/tiff-hul.html |title=JSTOR/Harvard Object Validation Environment - JHOVE TIFF-hul Module |access-date=2011-02-26 |url-status=dead |archive-url=https://web.archive.org/web/20101210133003/http://hul.harvard.edu/jhove/tiff-hul.html |archive-date=December 10, 2010 }}</ref><ref>{{cite web |url=http://tiki-lounge.com/~raf/tiff/tifffields.html |title=TIFF Fields |access-date=2011-02-27}}</ref><ref>{{cite web |url=http://www.digitalpreservation.gov/formats/content/tiff_tags.shtml |title=Tags for TIFF and Related Specifications |author=Library of Congress Collections |access-date=2011-02-27}}</ref><ref>{{cite web |url=http://docs.gimp.org/en/gimp-images-out.html#file-tiff-save |title=GIMP Documentation - Saving as TIFF |access-date=2011-02-27}}</ref><ref>{{cite web |url=http://www.irfanview.com/history_old.htm |title=IrfanView - History of changes |access-date=2011-02-27}}</ref>
|-
! Tag value
! Compression scheme
! Lossy/<wbr>lossless
! Specification
! Description
! Image types
! Usage and support
|-
| 0001<sub>16</sub> || None || Lossless || TIFF 6.0 || Baseline TIFF || All || {{yes|Common}}<ref>Commonly supported TIFF types can be displayed by image viewers such as [[Irfanview]]</ref>
|-
| 0002<sub>16</sub> || CCITT Group 3 1-Dimensional Modified Huffman run-length encoding (a.k.a. MH or CCITT 1D) || Lossless || TIFF 6.0 || Baseline TIFF; compression based on ITU-T T.4 || Black and white || {{yes|Common}}
|-
| 0003<sub>16</sub> || CCITT T.4 bi-level encoding as specified in section 4, Coding, of [//www.itu.int/rec/T-REC-T.4/en ITU-T Recommendation T.4] (a.k.a. CCITT Group 3 fax encoding or CCITT Group 3 2D) || Lossless || TIFF 6.0 || TIFF 6.0 Extensions; compression based on ITU-T T.4 || Black and white || {{yes|Common}}
|-
| 0004<sub>16</sub> || CCITT T.6 bi-level encoding as specified in section 2 of [//www.itu.int/rec/T-REC-T.6/en ITU-T Recommendation T.6] (a.k.a. [[Group 4 compression|CCITT Group 4 fax encoding]]) || Lossless || TIFF 6.0 || TIFF 6.0 extensions; compression based on ITU-T T.6 || Black and white || {{yes|Common}}
|-
| 0005<sub>16</sub> || [[Lempel–Ziv–Welch]] || Lossless || TIFF 6.0 || TIFF 6.0 Extensions; first defined in TIFF 5 (1988); a patented compression algorithm, but the patents expired in 2003 and 2004 || All || {{yes|Common}}<ref name="succeed">{{cite book|author=Succeed project|year= 2014|title=Recommendations for metadata and data formats for online availability and long-term preservation|url=http://www.succeed-project.eu/sites/default/files/deliverables/Succeed_600555_WP4_D4.1_RecommendationsOnFormatsAndStandards_v1.1.pdf|page=68|quote=If files are actively managed in a digital repository, it is possible to consider using either LZW or ZIP lossless compression for the TIFF files. JPEG compression should not be used within [...] TIFF. [...] Most of the respondents use uncompressed images (64%), if compression is used then LZW is mostly used.}}</ref>
|-
| 0006<sub>16</sub> || JPEG (obsolete 'old-style' JPEG, later superseded in Technote2) || Lossy || TIFF 6.0 || TIFF 6.0 Extensions; first defined in TIFF 6 (1992); obsolete, should never be written. || Continuous-tone || {{no|Rare}}
|-
| 0007<sub>16</sub> || JPEG ('new-style' JPEG) || Lossy || TIFF 6 Technote2 (1995) || supersedes old-style JPEG compression; it is a TIFF 6.0 extension. || Continuous-tone || {{partial|Uncommon}}
|-
| 0008<sub>16</sub> || Deflate (zlib), Adobe variant (official) || Lossless || TIFF Specification Supplement 2 (2002) || RFC 1950 (1996), RFC 1951 (1996), Adobe Photoshop TIFF Technical Notes; it is a TIFF 6.0 extension. || All || {{yes|Common}}
|-
| 0009<sub>16</sub> || JBIG, per [//www.itu.int/rec/T-REC-T.85/en ITU-T T.85] || Lossless || TIFF-FX || RFC 2301 (1998), RFC 3949 (2005) || Black and white || {{no|Rare}}
|-
| 000A<sub>16</sub> || JBIG, per [//www.itu.int/rec/T-REC-T.43/en ITU-T T.43] || Lossless  || TIFF-FX || RFC 2301 (1998), RFC 3949 (2005) || Black and white || {{no|Rare}}
|-
| 7FFE<sub>16</sub> || NeXT RLE 2-bit greyscale encoding ||  || Proprietary ||  ||  || {{no|Rare}}
|-
| 8005<sub>16</sub> || PackBits (a.k.a. Macintosh RLE) || Lossless || TIFF 6.0 || Baseline TIFF || All || {{no|Rare}}<ref name="succeed"/>
|-
| 8029<sub>16</sub> || ThunderScan RLE 4-bit encoding ||  || Proprietary ||  || Black and white || {{no|Rare}}
|-
| 807F<sub>16</sub> || RasterPadding in continuous tone (CT) or monochrome picture (MP) || Lossless || TIFF/IT (1998, 2004) || ISO 12639  ||  || {{no|Rare}}
|-
| 8080<sub>16</sub> || RLE for line work (LW) || Lossless || TIFF/IT (1998, 2004) || ISO 12639 ||  || {{no|Rare}}
|-
| 8081<sub>16</sub> || RLE for high-resolution continuous-tone (HC) || Lossless || TIFF/IT (1998, 2004) || ISO 12639 ||  || {{no|Rare}}
|-
| 8082<sub>16</sub> || RLE for binary line work (BL) || Lossless || TIFF/IT (1998, 2004) || ISO 12639 ||  || {{no|Rare}}
|-
| 80B2<sub>16</sub> || Deflate, PKZIP variant (obsolete) || Lossless || Proprietary || According to TIFF Specification Supplement 2 it should be considered obsolete but reading is recommended || All || {{partial|Uncommon}}
|-
| 80B3<sub>16</sub> || Kodak DCS ||  || Proprietary ||  ||  || {{no|Rare}}
|-
| 8765<sub>16</sub> || JBIG ||  || LibTIFF ||  || Black and white ||  {{no|Rare}}
|-
| 8798<sub>16</sub> || JPEG2000 ||  || Proprietary || Includes a complete JP2 file inside a TIFF file, not recommended.  Introduced by Leadtools.<ref>{{cite web | url=http://www.leadtools.com/sdk/formats/tiff.htm | title=LEADTOOLS TIFF SDK |access-date=2011-07-04 }}</ref>  ||  || {{partial|Uncommon}}
|-
| 8799<sub>16</sub> || Nikon NEF Compressed ||  || Proprietary ||  ||  || {{no|Rare}}
|-
| 879B<sub>16</sub> || [[JBIG2]] || Lossless, lossy || TIFF-FX Extension Set 1.0 || Abandoned IETF draft from 2001<ref>{{cite web | url=https://tools.ietf.org/html/draft-ietf-fax-tiff-fx-extension1-01 | title=Draft-ietf-fax-tiff-fx-extension1-01 }}</ref> ||  || {{no|Rare}}
|-
| 884C<sub>16</sub><ref name="dngSemanticMasks">{{citation|mode=cs1 |url=https://helpx.adobe.com/content/dam/help/en/photoshop/pdf/DNG_Spec_1_7_1_0.pdf#page=17 |page=17–18 |title=Digital Negative (DNG) Specification |date=September 2023 |version=1.7.1.0 |publisher=[[Adobe Inc]] |section=Semantic Masks}}</ref> || Lossy non-YCbCr JPEG || Lossy || [[Digital Negative|DNG]] 1.4.0.0<ref name="dngCompressionFormats">{{citation|mode=cs1 |url=https://helpx.adobe.com/content/dam/help/en/photoshop/pdf/DNG_Spec_1_7_1_0.pdf#page=20 |page=20–22 |title=Digital Negative (DNG) Specification |date=September 2023 |version=1.7.1.0 |publisher=[[Adobe Inc]] |section=Compression}}</ref> || Used for DNG semantic masks and for images in the {{code|LinearRaw}} colorspace; explicitly indicates baseline DCT JPEG compression as opposed to "lossless Huffman JPEG".<ref name="dngSemanticMasks"/><ref name="dngCompressionFormats"/> ||  || {{no|Rare}}
|-
| CD42<sub>16</sub><ref name="dngSemanticMasks"/> || [[JPEG XL]] || Lossless, lossy || DNG 1.7.0.0<ref name="dngCompressionFormats"/> ||  ||  || {{no|Rare}}
|}

==Related formats==
===BigTIFF===
<!-- Section header linked to from redirects -->
The TIFF file formats use [[32-bit computing#Range for storing integers|32-bit offsets]], which limits file size to around 4 [[Gibibyte|GiB]]. Some implementations even use a signed 32-bit offset, running into issues around 2 GiB. BigTIFF is a TIFF variant file format which uses 64-bit offsets and supports much larger files (up to 18 exabytes in size).<ref>{{Cite web|url=http://simplesystems.org/libtiff/bigtiffpr.html|title=Extending LibTiff library with support for the new format called BigTIFF|archive-url=https://web.archive.org/web/20220514114445/http://simplesystems.org/libtiff/bigtiffpr.html|archive-date=14 May 2022|url-status=dead}}</ref><ref>{{Cite web|url=https://www.awaresystems.be/imaging/tiff/bigtiff.html|title=The BigTIFF File Format|publisher=AWare Systems|archive-url=https://web.archive.org/web/20240706160214/https://www.awaresystems.be/imaging/tiff/bigtiff.html|archive-date=6 July 2024|url-status=dead}}</ref> The BigTIFF file format specification was implemented in 2007 in development releases of [[LibTIFF]] version 4.0, which was finally released as stable in December 2011. Support for BigTIFF file formats by applications is limited.

===Exif===
The [[Exif]] specification<ref>{{cite web |author=Technical Standardization Committee on AV & IT Storage Systems and Equipment |title=Exchangeable Image File Format for Digital Still Cameras |id=JEITA CP-3451 |version=Version 2.2 |publisher=[[Japan Electronics and Information Technology Industries Association]] |url=http://www.exif.org/Exif2-2.PDF |date=April 2002 |access-date=2024-09-05|archive-url=https://web.archive.org/web/20220428165430/http://www.exif.org/Exif2-2.PDF|archive-date=2022-04-28}}</ref> builds upon TIFF. For uncompressed image data, an Exif file is straight off a TIFF file with some private tags. For [[JPEG]] compressed image data, Exif uses the [[JPEG File Interchange Format]] but embeds a TIFF file in the APP1 segment of the file. The first IFD (termed 0th in the Exif specification) of that embedded TIFF does not contain image data, and only houses metadata for the primary image. There may however be a [[thumbnail]] image in that embedded TIFF, which is provided by the second IFD (termed 1st in the Exif specification). The Exif audio file format does not build upon TIFF.

Exif defines a large number of private tags for image metadata, particularly camera settings and [[geopositioning]] data, but most of those do not appear in the ordinary TIFF IFDs. Instead these reside in separate IFDs which are pointed at by private tags in the main IFD.

=== TIFF/IT ===
<!-- Section header linked to from redirects -->
{{Infobox file format
| name = TIFF/IT
| extension = .fp, .ct, .lw, .hc, .mp, .bp, .bl, .sd<ref name="jdf">{{cite web |url=http://www.cip4.org/documents/jdf_specifications/html/APPX_MimeType_and_MimeTypeVersion_attributes.html |title=JDF Specification - Appendix H MimeType and MimeTypeVersion Attributes |author=CIP4 |year=2008 |access-date=2011-03-03}}</ref>
| mime = not defined<ref name="jdf" />
| type code =
| uniform type =
| owner = ANSI, ISO
| released = {{start date|1993}}
| latest release version = TIFF/IT
| latest release date    = {{Start date and age|2004|df=yes}}
| genre = [[Image file formats|Image file format]]
| container for =
| contained by =
| extended from = TIFF 6.0
| extended to =
| standard = ISO 12639<ref name="TIFF/IT" /><ref>{{cite web |url=http://webstore.ansi.org/RecordDetail.aspx?Sku=ISO%2012639:2004&PageType=2 |title=ISO 12639:2004 - Graphic technology - Prepress digital data exchange - Tag image file format for image technology (TIFF/IT) |access-date=2011-03-03}}</ref><ref name="dis12639">{{citation |url=http://licencepro.estienne.free.fr/Normes/tiffIT_p2.pdf |title=DRAFT INTERNATIONAL STANDARD ISO/DIS 12639 - Graphic technology — Prepress digital data exchange — Tag image file format for image technology (TIFF/IT) - Revision of first edition (ISO 12639:1998) |author=ISO |year=2002 |access-date=2011-03-07}}</ref>
}}
TIFF/IT is used to send data for print-ready pages that have been designed on high-end prepress systems.<ref>{{cite web |url=http://www.printingtips.com/glossary-term/t--2360/tiffit.asp |title=Glossary of Printing Terms - TIFF/IT |access-date=2011-03-01}}</ref> The TIFF/IT specification (ISO 12639) describes a multiple-file format, which can describe a single page per file set.<ref>{{citation |url=http://www.cip4.org/documents/ppf_specifications/cip3embd_v1_0.pdf |title=CIP3 application note |access-date=2011-03-01}}</ref> TIFF/IT files are not interchangeable with common TIFF files.<ref name="rmg">{{citation |url=http://www.rgmgraphics.com/Tiff-It.pdf |title=Tiff/It Questions and Answers |access-date=2011-03-01}}</ref><ref name="issuu">{{citation |url=http://issuu.com/michaelejahn/docs/jahn_introtopdfx_fontsembed |title=Introduction to PDF/X |access-date=2011-03-01}}</ref><ref>{{cite web |url=http://www.interviewmagspecs.com/Pages/Tiff_It_P1_Specs.html |title=Tiff/It P1 Specifications |quote=Note: TIFF/IT-P1 is not equivalent to a Photoshop® Tiff! |access-date=2011-03-03}}</ref>

The goals in developing TIFF/IT were to carry forward the original [[IT8]] magnetic-tape formats into a medium-independent version. TIFF/IT is based on Adobe TIFF 6.0 specification and both extends TIFF 6, by adding additional tags, and restricts, it by limiting some tags and the values within tags. Not all valid TIFF/IT images are valid TIFF 6.0 images.<ref name="ipa" />

TIFF/IT defines image-file formats for encoding color continuous-tone picture images, color [[line art]] images, high-resolution continuous-tone images, monochrome continuous-tone images, binary picture images, binary line-art images, screened data, and images of composite final pages.<ref name="TIFF/IT2" />

There is no MIME type defined for TIFF/IT. The MIME type ''image/tiff'' should not be used for TIFF/IT files, because TIFF/IT does not conform to Baseline TIFF 6.0 and the widely deployed TIFF 6.0 readers cannot read TIFF/IT. The MIME type ''image/tiff'' (defined in RFC 3302) without an application parameter is used for Baseline TIFF 6.0 files or to indicate that it is not necessary to identify a specific subset of TIFF or TIFF extensions. The application parameter should be used with ''image/tiff'' to distinguish TIFF extensions or TIFF subsets. According to RFC 3302, specific TIFF subsets or TIFF extensions must be published as an RFC. There is no such RFC for TIFF/IT. There is also no plan by the ISO committee that oversees TIFF/IT standard to register TIFF/IT with either a parameter to image/tiff or as new separate MIME type.<ref name="jdf" />

==== TIFF/IT files ====
TIFF/IT consists of a number of different files and it cannot be created or opened by common desktop applications.<ref name="jdf" /><ref name="rmg" /><ref>{{cite web|url=http://www.ddap.org/resource_center/tiffit_implementers.php |title=TIFF/IT Implementers |year=2003 |author=DDAP Association |access-date=2011-03-03 |url-status=unfit |archive-url=https://web.archive.org/web/20050425150213/http://www.ddap.org/resource_center/tiffit_implementers.php |archive-date=April 25, 2005 }}</ref> TIFF/IT-P1 file sets usually consist of the following files:<ref name="TIFF/IT2" /><ref name="prepressure-tiffit" /><ref name="xitron">{{citation|url=http://www.xitron.com/downloads/support/technical_documents/plugin_manuals/tiffitp1out.pdf |title=Harlequin RIP - manual for a commercial TIFF/IT plugin |access-date=2011-03-02 |url-status=dead |archive-url=https://web.archive.org/web/20110220205500/http://www.xitron.com/downloads/support/technical_documents/plugin_manuals/tiffitp1out.pdf |archive-date=February 20, 2011 }}</ref>
* Final Page (FP)
* Continuous Tone image (CT)
* Line Work image (LW)
* High resolution Continuous-tone files (HC - optional)
TIFF/IT also defines the following files:<ref name="TIFF/IT2" />
* Monochrome continuous-tone Picture images (MP)
* Binary Picture images (BP)
* Binary Line-art images (BL)
* Screened Data (SD)

Some of these data types are partly compatible with the corresponding definitions in the TIFF 6.0 specification. The Final Page (FP) allows the various files needed to define a complete page to be grouped together: it provides a mechanism for creating a package that includes separate image layers (of types CT, LW, etc.) to be combined to create the final printed image. Its use is recommended but not required. There must be at least one subfile in an FP file, but no more than one of each type. It typically contains a CT subfile and an LW subfile.<ref name="TIFF/IT2" /><ref name="ipa" /><ref name="harl8">{{citation|url=http://www.rti-rips.com/LinkedDocuments/Version8Manuals/Harlequin_RIP_Manual_Mac.pdf |title=A software manual with information about TIFF/IT |url-status=dead |archive-url=https://web.archive.org/web/20110920084616/http://www.rti-rips.com/LinkedDocuments/Version8Manuals/Harlequin_RIP_Manual_Mac.pdf |archive-date=September 20, 2011 }}</ref>

The primary color space for this standard is CMYK, but also other color spaces and the use of ICC Profiles are supported.<ref name="TIFF/IT2" />

==== TIFF/IT compression ====
TIFF/IT makes no provision for compression within the file structure itself, but there are no restrictions.<ref name="ipa" /> (For example, it is allowed to compress the whole file structure in a ZIP archive.)

LW files use a specific compression scheme known as Run-length encoding for LW (Compression tag value is 8080<sub>16</sub>). HC files also use a specific Run-length encoding for HC (Compression tag value is 8081<sub>16</sub>). The TIFF/IT P1 specs do not allow use of compression within the CT file.

The following is a list of defined TIFF/IT compression schemes:<ref name="dis12639" />

{|class="wikitable sortable" style="width: 100%"
|+TIFF/IT compression schemes
|-
! File type !! TIFF/IT conformance !! TIFF/IT-P1 conformance !! TIFF/IT-P2 conformance
|-
| Final Page (FP) 0th IFD field || colspan="3" style="text-align: center;" | Uncompressed (0001<sub>16</sub>), Deflate (0008<sub>16</sub>) or PackBits (8005<sub>16</sub>)
|-
| Continuous Tone (CT) || Uncompressed (0001<sub>16</sub>), JPEG (0007<sub>16</sub>), Deflate (0008<sub>16</sub>) or RasterPadding in CT or MP (807F<sub>16</sub>) || Uncompressed (0001<sub>16</sub>) || Uncompressed (0001<sub>16</sub>), JPEG (0007<sub>16</sub>), Deflate (0008<sub>16</sub>)
|-
| Line Work (LW) || colspan="3" style="text-align: center;" | RLE for LW (8080<sub>16</sub>)
|-
| High resolution Continuous tone (HC) || colspan="3" style="text-align: center;" | RLE for HC (8081<sub>16</sub>)
|-
| Monochrome continuous-tone Picture (MP) || Uncompressed (0001<sub>16</sub>), JPEG (0007<sub>16</sub>), Deflate (0008<sub>16</sub>) or RasterPadding in CT or MP (807F<sub>16</sub>) || Uncompressed (0001<sub>16</sub>) || Uncompressed (0001<sub>16</sub>), JPEG (0007<sub>16</sub>), Deflate (0008<sub>16</sub>)
|-
| Binary Picture images (BP) || Uncompressed (0001<sub>16</sub>), CCITT T.6 bi-level encoding (0004<sub>16</sub>), Deflate (0008<sub>16</sub>) || Uncompressed (0001<sub>16</sub>) || Uncompressed (0001<sub>16</sub>), CCITT T.6 bi-level encoding (0004<sub>16</sub>), Deflate (0008<sub>16</sub>)
|-
| Binary Line art (BL) || colspan="2" style="text-align: center;" | RLE for BL (8082<sub>16</sub>) ||
|-
| Screened Data (SD) || Uncompressed (0001<sub>16</sub>), CCITT T.6 bi-level encoding (0004<sub>16</sub>), Deflate (0008<sub>16</sub>) ||   || Uncompressed (0001<sub>16</sub>), CCITT T.6 bi-level encoding (0004<sub>16</sub>), Deflate (0008<sub>16</sub>)
|}

====TIFF/IT P1====
<!-- Section header linked to from redirects -->
The ISO 12639:1998 introduced TIFF/IT-P1 (Profile 1) - a direct subset of the full TIFF/IT standard (previously defined in ANSI IT8.8–1993). This subset was developed on the ground of the mutual realization by both the standards and the software development communities that an implementation of the full TIFF/IT standard by any one vendor was both unlikely (because of its complexity), and unnecessary (because Profile 1 would cover most applications for digital ad delivery). Almost all TIFF/IT files in digital advertising were distributed as TIFF/IT-P1 file sets in 2001.<ref>{{citation |url=http://www.ddap.org/resource_center/tiffit_position_paper.php |title=DDAP Position Statement - TIFF/IT as a File Format for Delivery of Digital Advertising - October, 2001 |date=October 2001 |access-date=2011-03-03 |archive-url=https://web.archive.org/web/20040111002537/http://www.ddap.org/resource_center/tiffit_position_paper.php |archive-date=2004-01-11}}</ref><ref>{{citation|url=http://www.ddap.org/resources/white_papers/TIFFITPosition.pdf |title=DDAP Position Statement - TIFF/IT as a File Format for Delivery of Digital Advertising - October, 2001 |date=October 2001 |access-date=2011-03-03 |url-status=unfit |archive-url=https://web.archive.org/web/20030321070342/http://www.ddap.org/resources/white_papers/TIFFITPosition.pdf |archive-date=March 21, 2003 }}</ref> When people talk about TIFF/IT, they usually mean the P1 standard.<ref name="prepressure-tiffit" />

Here are some of the restrictions on TIFF/IT-P1 (compared to TIFF/IT):<ref name="harl8" />
* Uses CMYK only (when appropriate)
* It is pixel interleaved (when appropriate)
* Has a single choice of image orientation
* Has a single choice of dot range
* Restricted compression methods

TIFF/IT-P1 is a simplified conformance level of TIFF/IT and it maximizes the compatibility between Color Electronic Prepress Systems (CEPS) and Desk Top Publishing (DTP) worlds.<ref name="ipa">{{citation|url=http://www.ipa.org/pdf/bulletin/ddap_tiff_pdf.pdf |title=DDAP, TIFF/IT-P1, PDF-X/1 |year=1998 |access-date=2011-03-01 |url-status=dead |archive-url=https://web.archive.org/web/20060215234111/http://www.ipa.org/pdf/bulletin/ddap_tiff_pdf.pdf |archive-date=February 15, 2006 }}</ref><ref name="tiffitonline">{{cite web |url=http://tiffit-online.com/about.html |title=TIFF/IT-P1 |access-date=2011-03-01}}</ref> It provides a clean interface for the proprietary CEPS formats such as the [[Scitex CT]]/LW format.

====TIFF/IT P2====
<!-- Section header linked to from redirects -->
Because TIFF/IT P1 had a number of limitations, an extended format was developed. The ISO 12639:2004 introduced a new extended conformance level - TIFF/IT-P2 (Profile 2). TIFF/IT-P2 added a number of functions to TIFF/IT-P1 like:<ref name="prepressure-tiffit" />
* CMYK spot colors only (when appropriate)
* Support for the compression of CT and BP data (JPEG and Deflate)
* Support for multiple LW and CT files in a single file
* Support for copydot files through a new file type called SD (Screened Data)
* There was some effort to create a possibility to concatenate FP, LW, and CT files into a single file called the GF (Group Final) file, but this was not defined in a draft version of ISO 12639:2004.<ref name="dis12639" />

This format was not widely used.

==== Private tags ====
The TIFF/IT specification preserved the TIFF possibility for developers to utilize private tags. The TIFF/IT specification is very precise regarding how these private tags should be treated - they should be parsed, but ignored.<ref name="tiffitprivatetags">{{cite web|url=http://www.ddap.com/resources/privatetags_faqs.html |title=TIFF/IT Private Tags |author=DDAP Association |year=2002 |access-date=2011-03-03 |url-status=unfit |archive-url=https://web.archive.org/web/20030428202922/http://www.ddap.com/resources/privatetags_faqs.html |archive-date=April 28, 2003 }}</ref>

Private tags in the TIFF/IT-P1 specification were originally intended to provide developers with ways to add specific functionality for specific applications. Private tags can be used by developers (e.g., Scitex) to preserve specific printing values or other functionality. Private tags are typically labelled with tag numbers greater than or equal to 32768.

All private tags must be requested from Adobe (the TIFF administrator) and registered.

In 1992, the DDAP (Digital Distribution of Advertising for Publication, later Digital Directions in Applications for Production) developed their requirement statement for digital ad delivery. This was presented to  ANSI-accredited CGATS (Committee for Graphic Arts Technology Standards) for development of an accredited file format standard for the delivery of digital ads. CGATS reviewed their alternatives for this purpose and TIFF seemed like the ideal candidate, except for the fact that it could not handle certain required functionalities. CGATS asked Aldus (the TIFF administrator) for a block of their own TIFF private tags in order to implement what eventually became TIFF/IT. For example, the ability to identify the sequence of the colors is handled by tag 34017 - the Color Sequence Tag.<ref name="tiffitprivatetags" />

TIFF/IT was created to satisfy the need for a transport-independent method of encoding raster data in the IT8.1,
IT8.2 and IT8.5 standards.

==== Standards ====
TIFF/IT was defined in ANSI IT8.8–1993 standard in 1993 and later revised in the International Standard ''ISO 12639:1998 - Prepress digital data exchange – Tag image file format for image technology (TIFF/IT)''.<ref name="TIFF/IT" /> The ISO standard replaces ANSI IT8.8–1993. It specifies a media-independent means for prepress electronic data exchange.<ref>{{cite web |url=http://www.printingtips.com/email-term/t--2361/tiffitp1.asp |title=Glossary of Printing Terms - TIFF/IT-P1 |access-date=2011-03-01}}</ref>

The ISO 12639:2004 (Second edition) standard for TIFF/IT superseded the ISO 12639:1998. It was also later extended in ISO 12639:2004 / Amd. 1:2007 - Use of JBIG2-Amd2 compression in TIFF/IT.<ref>{{Cite web|url=https://www.iso.org/cms/render/live/en/sites/isoorg/contents/data/standard/03/43/34342.html|title=ISO 12639:2004|website=ISO|language=en|access-date=2020-04-19}}</ref>

==See also==
{{commons category|Tagged Image File Format}}
*[[Comparison of graphics file formats]]
*[[LibTIFF]], widely used open source library + utilities for reading/writing/manipulating TIFF files
*[[Digital Negative (file format)|DNG]]
*[[GeoTIFF]]
*[[Image file formats]]
*[[STDU Viewer]]
*[[Windows Photo Viewer]]
*[[T.37 (ITU-T recommendation)]]

==References==
{{reflist|30em}}

== External links ==
*[https://web.archive.org/web/20210108172855/https://www.adobe.io/open/standards/TIFF.html Adobe TIFF Resources page]: Adobe links to the specification and main TIFF resources
*[http://simplesystems.org/libtiff/ LibTIFF Home Page]: Widely used library used for reading and writing TIFF files as well as TIFF file processing command line tools
*[http://www.awaresystems.be/imaging/tiff.html TIFF File Format FAQ and TIFF Tag Reference]: Everything you always wanted to know about the TIFF File Format but were afraid to ask
*[http://www.digitalpreservation.gov/formats/fdd/fdd000022.shtml TIFF description] at Digital Preservation (The Library of Congress)
*[http://cool.conservation-us.org/bytopic/imaging/std/tiff4.html TIFF Revision 4.0]: Specification for revision 4.0, in HTML (warning: for historical purposes only, the TIFF 6.0 spec contains the full 4.0 revision)
*[http://cool.conservation-us.org/bytopic/imaging/std/tiff5.html TIFF Revision 5.0]: Specification for revision 5.0, in HTML (warning: for historical purposes only, the TIFF 6.0 spec contains the full 5.0 revision)
*[https://web.archive.org/web/20210108174645/https://www.adobe.io/content/dam/udp/en/open/standards/tiff/TIFF6.pdf TIFF Revision 6.0]: Specification for revision 6.0, in PDF (warning: there is an outdated and flawed section (jpeg compression), corrected in supplements, and there are additions to this PDF too – for the full specification, see the [https://web.archive.org/web/20210108172855/https://www.adobe.io/open/standards/TIFF.html Adobe TIFF Resources page]
* {{IETF RFC|3302|link=no}} - image/tiff, {{IETF RFC|3949|link=no}} and {{IETF RFC|3950|link=no}} - image/tiff-fx, {{IETF RFC|2306|link=no}} - Tag Image File Format (TIFF) - F Profile for Facsimile, {{IETF RFC|1314|link=no}} - legacy exchange of images in the Internet.
*[http://www.mathworks.com/matlabcentral/fileexchange/36958 Code Tiff Tag Reader] - Easy readable code of a TIFF tag reader in Mathworks Matlab (Tiff 5.0/6.0)
*[http://www.alternatiff.com/ AlternaTIFF]  - Free in-browser TIFF viewer
* eiStream Annotation (also known as Wang or Kodak Annotation). Developed by eiStream.
**{{cite web | url=http://www5.eistream.com/support_pro/faqs/annospec.htm | archive-url=https://web.archive.org/web/20030124024322/http://www5.eistream.com/support_pro/faqs/annospec.htm | archive-date=2003-01-24 | title=eiStream Annotation Specification, Version 1.00.06 |access-date=2013-05-14 }}
* ADEO Imaging Annotation
** {{cite web | url=http://www.adeoimaging.com | title=Multi-Page TIFF Editor - History of changes - TIFF tags |access-date=2013-05-14 }}

{{Compression formats}}
{{Graphics file formats}}

[[Category:High dynamic range file formats]]
[[Category:Raster graphics file formats]]
[[Category:Adobe Inc.]]