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Limitations: There are no provisions in TIFF for storing vector graphics, text annotation, etc (although such items could be easily constructed using TIFF extensions), and so if this is a requirement you would be better off with a format with broader scope, such as PostScript, CGM, or PICT. TIFF is based on file-offsets, so that it is not easily "streamable" in the way JPEG JFIF streams are.
A common complaint of TIFF is rooted in its flexibility. For example the TIFF format permits both MSB ("Motorola") and LSB ("Intel") byte order data to be stored, with a header item indicating which order is used. There are old, poorly written TIFF programs on the PC which rebelled against this and assume that all TIFF files are Intel byte order. It is very easy to write a TIFF-writer, but very difficult to write a fully TIFF compliant reader.
TIFF uses 4-byte integer file offsets to store image data, with the consequence that a TIFF file cannot have more than 4 Gigabytes of raster data (and some files have begun to approach this boundary). However, this is 4G of compressed data, and so if the compression ratio is high enough, theoretically a TIFF image could be much larger (in fact, 2**32-1 pixels square).
Strengths: TIFF is primarily designed for raster data interchange. It's main strengths are a highly flexible and platform-independent format which is supported by numerous image processing applications. Since it was designed by developers of printers, scanners and monitors, it has a very rich space of information elements for colorimetry calibration, gamut tables, etc. Such information is also very useful for remote sensing and multispectral applications.
Another feature of TIFF which is also useful is the ability to decompose an image by tiles rather than scanlines. This permits much more efficient access to very large imagery which has been compressed (since one does not have to decompress an entire scanline).
Theoretically, TIFF can support imagery with multiple bands (up to 64K bands), arbitrary # bits per pixel, data cubes, and multiple images per file, including thumbnail subsampled images.
Color spaces supported include
TIFF is a trademark, formerly registered to Aldus, and which is now claimed (though not yet registered) by Adobe Systems, Inc.
TIFF tag and TIFF compression ID registration is handled by Adobe Developer Relations. Please send your requests to Adobe developer relations support staff at:
gapdevsup@adobe.comAdobe needs the following information to assign a TIFF tag or compression code:
Company Name: Contact Name: Address: Phone: Fax: Email: Brief description of tag format (optional, see below):It is their policy not to divulge information about TIFF tag owners or the format of private tag data without the owner's consent. If you wish to make public the fact that you are the owner of a tag and/or details about a tag's layout, you can send them this information and they will store it in their TIFF registration database.
To: tiff-request@olympiakos.com
Subject: none
subscribe tiff
(optionally, after "subscribe tiff" you may place an email address). You
will receive a confirmation from the Majordomo listserver running there. To post
messages, send email to tiff@olympiakos.com.
There is also a mailing list for discussing the GeoTIFF TIFF tag extensions for georeferenced raster data, which can be accessed by sending email:
To: geotiff-request@mtmorrison.jpl.nasa.gov
Subject: none
subscribe geotiff Your-Name-Here
An archive. of the
ongoing GeoTIFF list discussion is now available.
A compressed PostScript version of the spec is available from the SGI TIFF archive, which also has an uncompressed version.
Older Revision Specs are also online (for historians, only!):
See also the "Extensions"
section on the freeware "Zip-in-TIFF" alternative proposed. The LIBTIFF.ORG Page for the libtiff
package is here.
Unix-style manual
pages for the suboutines and utilities are also now online.
There is a hacked version of Libtiff for Windows-flavored compilers,
allowing the creation of DLL's, and is called LIBTIFFW. The
cognizant programmer is Soren Pingel
Dalsgaard.
XV Viewer by John Bradley is
a very nice display program, which has some nice editing features, and a
"Visual Schauzer" which provides a icon/desktop view of a directory, with
thumbnails, etc. Note, however, that the most recent versions are *NOT* public
domain, but must be licensed. The source code is also available, and it uses
the "libtiff" package.
See also the Unix
and X-windows entry of the comp.graphics FAQ archive. There are a lot of TIFF programs in the SimTel archives:
On a related note, see also the PNG (Portable Network Graphics) Web
page, for another format using Zip and zlib.
Caveat: the Zip-TIFF approach has not been adopted widely, as yet.
However, Adobe technical support has expressed the intention to include it in
the next TIFF 7.0 specification (to be released Real Soon Now (TM)).
See also the Facsimile (Fax)
SubSection of the WWW
Virtual Library for more information.
TIFF Fax Viewers are available at:
Note: TIFF/IT = Transport Independent File Format for Image
Technology.
It is intended that the TIFF/IT standard will reduce the variation between
TIFF implementations which has led to a reputation of valid TIFF files often
being unreadable when transferred between different applications.
The TIFF/IT spec is available from the ANSI standards organization or NPES,
the association of suppliers of printing and publishing technologies. It is
ANSI standard IT8.8-1993 'Tag image format for image technology' NPES's phone
number in the United States is (703) 264-7200.
RFC 1314
concerns suggested standards for using TIFF for document interchange on the
Internet. The standard is compared with the "TIFF Class F" fax scheme. TIFF Online
Test Images. If you have a TIFF viewer linked to your Web Browser, you can
test it on these images. Sources for TIFF viewers is also provided.
What programs can read Multi-page TIFF?
Here are some
programs that have been used by readers of the TIFF mailing list:
Is the LZW Compression in TIFF patented?
Yep; Unisys holds a patent on the
compression algorithm, which is the same as the one used in Compuserve's GIF
format. For more information, see the Graphics
File Format FAQ entry, which has further details and pointers to the
patents and licensing agreements.
Where can I find Public TIFF Software ?
TIFF Libraries and Source Code
LIBTIFF
Sam Leffler has written a
platform-independent, public-domain subroutine library and tool-set for TIFF
files, called "libtiff".
LIBTIFF
TIFF256
Graphics Library is a shareware, licensable TIFF library supporting TIFF
5.0 (the latest rev is 6.0). Don't know much about it.
WOCAR: Optical Character Recognition (OCR) for TIFF
WOCAR
is an Optical Characters Recognition Application (OCR). It converts scanned
documents to text documents. The software can process documents written in
English or in French. WOCAR can work with any scanner that supports the TWAIN
interface. It can also process any bilevel TIFF image file. (multipage TIFF
files are supported) This application works on Windows 95 and Windows NT, and
is also availabe at the Simtelnet
FTP site. The author of this package is Cyril Cambien, who also has his own web page.
ImTool package
The ImTools
converter put out by the San Diego Supercomputer Center claims to be able to
handle "many tiff formats that others can't". Try it out and let me know.
SimTel package
SimTel TIFF package
Software, source code, etc available, primarily for MS-DOS platforms. It
includes the original TIFF library put out by Aldus, and looks to be rather
outdated, and unlikely to support TIFF 6.0 additions, such as tiling.
Comp.Graphics Archives
The Usenet
Comp.Graphics FAQ files is an excellent resource for finding TIFF viewers,
converters, etc. Discussions arising in the comp.graphics.* newsgroups
about pros and cons for other formats, the "LZW" patent issues, etc are also
included. In particular the section on Image
Conversion and Display programs is very useful. Most of the references
below are extracted from this reference.
Viewers and Editors
Macintosh
One of the best public-domain TIFF viewers for the mac is also a very nice
image-processing system in its own right, called NIH Image. It now supports
Adobe Photoshop plug-ins as well, and can display most garden-variety TIFF
files, though older versions had problems with "tiled" TIFF images. And yes,
it will handle 16-bit grayscale TIFF, if need be. It is limited to 8-bit color
display, but given a 24-bit RGB it will allow you to edit the color planes
separately, and view "palettized" version of the color data. Pascal Source
code for Metrowerks CW7 or later is also available for hacking.
Unix Boxes/X
ImageMagick
can open most TIFF files, and do some annotation, using the standard X-window
interface. It is in the public domain.
PC/DOS/Windows Flavored Systems
I don't have any personal experience with these systems, but your best bet
is to refer to the MS-DOS
Image Viewers or the Windows
and OS/2 entries of the comp.graphics FAQ archives. Note, however, that
some of the links are out of date.
What TIFF Extensions are Available?
TIFF is a
very extensible format, and there are a number of efforts to extend TIFF for
specific applications by registering new tags with Adobe. A number of such
extensions are described below:
GeoTIFF
GeoTIFF is a
newly emerging interchange standard, which permits the addition of Geographic
information such as projections, datums, etc, associated with remote sensing
or cartographic raster data.
Adobe Extensions for PageMaker
Adobe has recently defined a set of extensions
to the TIFF spec, allowing for "clipping-path" definitions, etc.
JPEG - in - TIFF
Another effort involves the encapsulation of a decent lossy JPEG stream
within TIFF; the original 6.0 spec was not worked out correctly. Tom Lane led
the development of the new TIFF implementation called JPEG-in-TIFF. The
current libtiff
package offers some level of JPEG support, when linked with the IJG JPEG
library, available at ftp://ftp.uu.net/graphics/jpeg/ (if
you can ever get in), or at ftp://ftp.cs.wisc.edu/ghost/. See also
Tom Lane's JPEG
Frequently Asked Questions file.
Zip - in - TIFF
The best lossless compression scheme in TIFF currently is LZW (Lempel Ziv
Welch), which, unfortunately, suffers from the same Unisys patent problems
as the popular "GIF" format. For this reason, an alternative, non-proprietary
compression scheme has been proposed, based on the ZLIB/Deflation
stream. The current libtiff package
offers some level of Zip support, when linked with the zlib library, available
at the ftp://ftp.uu.net/pub/archiving/zip/zlib/
archives, the. www-dsed.llnl.gov
archives, and the swrinde.nde.swri.edu
archive (in Zip format). The current version level is 1.0.4, as of 21
November, 1996.
TIFF Class F Revised Specification
The TIFF
Class F Revised Specification documents the TIFF spec tags specific to FAX
applications. RFC 804 covers
the RFC on the CCITT Recommendation T.4 which explains CCITT Group 3 encoding
and the Modified Huffman and Modified Read compression algorithms.
TIFF/IT Prepress Interchange Standard
The Raster Graphic
Interchange Standards page has a link to information on TIFF/IT standard for
prepress applications.
TIFF enhancements for Adobe PageMaker 6.0
This Technical
Note includes new TIFF tags for supporting such things as TIFF directory
"Trees" (as opposed to the singly-linked list of IFD's), defining polygonal
"clipping paths" (ala PostScript), indexed ("palette") images for other color
spaces such as CMYK, and a definition of the new ICC L*a*b* color space.
RichTIFF
The RichTIFF
standard was defined by Crosfield , now maintained by ITPC, and was
designed primarily for newsphoto interchange. RichTIFF is not really a
standard format, but rather a guideline on how to format TIFF files for this
purpose.
Wang TIFF Image-Annotation extensions
Wang has developed some tag
extensions for TIFF files, including post-it notes etc. It is very Wintel
specific, but you may find it useful.
Kodak TIFF extensions
Kodak has several file formats in use which are more or less based on the
TIFF spec (though not always complying with the strict rules). The Kodak
Professional Digital Camera System produces a file with TIFF header and
multiple IFD's of various types, and there is also a "KIFF" (Kodak Image File
Format) based on TIFF with proprietary colorspace and compression methods (the
use of which changes their name to "KIC" - Kodak Image Compression - files.
For more information contact Kodak
directly.
Internet RFC's Related to TIFF
RFC 804 covers the RFC on the CCITT Recommendation T.4 which explains
CCITT Group 3 encoding and the Modified Huffman and Modified Read compression
algorithms. (Group 4 is detailed in CCITT Recommendation T.6).
Other TIFF Related Pages
Last modified: Feb 14, 1997
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