Editing TIFF (section)

=== TIFF/IT ===
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{{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====
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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 |archive-url=https://web.archive.org/web/20010418033216/http://www.tiffit-online.com/about.html |url-status=usurped |archive-date=April 18, 2001 |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====
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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>