Tag Image File Format Fax eXtended (TIFF-FX) - image/tiff-fx MIME Sub-type Registration
Official registration of a MIME type for fax images in TIFF-FX format.
McIntyre, L., Parsons, G., and J. Rafferty, "Tag Image File Format Fax eXtended (TIFF-FX) - image/tiff-fx MIME Sub-type Registration", RFC 3250, DOI 10.17487/RFC3250, September 2002, <https://www.rfc-editor.org/info/rfc3250>.
@misc{rfc3250,
series = {Request for Comments},
number = 3250,
howpublished = {RFC 3250},
publisher = {RFC Editor},
doi = {10.17487/RFC3250},
url = {https://www.rfc-editor.org/info/rfc3250},
author = {L. McIntyre and G. Parsons and J. Rafferty},
title = {{Tag Image File Format Fax eXtended (TIFF-FX) - image/tiff-fx MIME Sub-type Registration}},
pagetotal = 7,
year = 2002,
month = sep,
} RFC text
Contents
Network Working Group L. McIntyre
Request for Comments: 3250 Xerox Corporation
Category: Standards Track G. Parsons
Nortel Networks
J. Rafferty
Brooktrout Technology
September 2002
Tag Image File Format Fax eXtended (TIFF-FX) - image/tiff-fx
MIME Sub-type Registration
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2002). All Rights Reserved.
Abstract
This document describes the registration of the MIME sub-type
image/tiff-fx. The encodings are defined by File Format for Internet
Fax and its extensions.
1. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC-2119 [REQ].
2. Overview
This document describes the registration of the MIME sub-type
image/tiff-fx. The encodings are defined by File Format for Internet
Fax [TIFF-FX] and its extensions.
3. Internet Fax Working Group
This document is a product of the IETF Internet Fax Working Group.
All comments on this document should be forwarded to the email
distribution list at <ietf-fax@imc.org>.
3. TIFF-FX Definition
TIFF-FX (Tag Image File Format Fax eXtended), is defined in detail by
RFC 2301 "File Format for Internet Fax" [TIFF-FX].
While a brief scope and feature description is provided in this
section as background information, the reader is directed to the
original TIFF-FX specification (File Format for Internet Fax) to
obtain complete feature and technical details.
3.1 TIFF-FX Scope
This document defines a TIFF-based file format specification for
enabling standardized messaging-based fax over the Internet. It
specifies the TIFF fields and field values required for compatibility
with the existing ITU-T Recommendations for Group 3 black-and-white,
grayscale and color facsimile. TIFF has historically been used for
handling fax image files in applications such as store-and-forward
messaging. Implementations that support this file format
specification for import/export may elect to support it as a native
format. This document recommends a TIFF file structure that is
compatible with low-memory and page-level streaming implementations.
Unless otherwise noted, the current TIFF specification [TIFF] and
selected TIFF Technical Notes [TTN1, TTN2] are the primary references
for describing TIFF and defining TIFF fields. This document is the
primary reference for defining TIFF field values for fax
applications.
3.2 TIFF-FX Features
Some of the features of TIFF-FX are:
- TIFF-FX is capable of describing bilevel, grayscale, palette-
color, full-color and mixed content image data.
- TIFF-FX includes a number of compression schemes that allow
developers to choose the best space or time tradeoff for their
applications.
- TIFF-FX is designed to be extensible and to evolve gracefully
as new needs arise.
4. MIME Definition
This document defines the image/tiff-fx MIME sub-type to refer to
TIFF-FX Profiles J, C, L and M encoded image data and any future
TIFF-FX extensions, or a subset. The image/tiff-fx content type may
be used when black-and-white image data is encoded using TIFF-FX
Profiles S or F, or a subset.
5. IANA Registration
To: ietf-types@iana.org
Subject: Registration of Standard MIME media type image/tiff-fx
MIME media type name: image
MIME subtype name: tiff-fx
Required parameters: none
Optional parameters: none
Encoding Considerations: This media type consists of binary
data. The base64 encoding should be used on transports that
cannot accommodate binary data directly.
Security considerations:
TIFF-FX utilizes a structure which can store image data and
attributes of this image data. The fields defined in the
TIFF-FX specification are of a descriptive nature and provide
information that is useful to facilitate viewing and
rendering of images by a recipient. As such, the fields
currently defined in the TIFF-FX specification do not in
themselves create additional security risks, since the
fields are not used to induce any particular behavior by the
recipient application.
TIFF-FX has an extensible structure, so that it is
theoretically possible that fields could be defined in the
future which could be used to induce particular actions on
the part of the recipient, thus presenting additional
security risks, but this type of capability is not supported
in the referenced TIFF-FX specification. Indeed, the
definition of fields which would include such processing
instructions is inconsistent with the goals and spirit of the
TIFF-FX specification.
Interoperability considerations:
The ability of implementations to handle all the defined
applications (or profiles within applications) of TIFF-FX may
not be ubiquitous. As a result, implementations may decode
and attempt to display the encoded TIFF-FX image data only to
determine that the image cannot be rendered.
Published specification:
TIFF-FX (Tag Image File Format Fax eXtended) is defined in:
RFC 2301 "File Format for Internet Fax", January 1998
McIntyre, L., Zilles, S., Buckley, R., Venable, D.,
Parsons, G., and J. Rafferty.
Applications which use this media type:
Imaging, fax, messaging and multi-media
Additional information:
Magic number(s):
II (little-endian): 49 49 2A 00 hex
MM (big-endian): 4D 4D 00 2A hex
File extension(s): .TFX
Macintosh File Type Code(s): TFX
Person & email address to contact for further information:
Lloyd McIntyre
lmcintyre@xerox.com
Glenn W. Parsons
gparsons@nortelnetworks.com
James Rafferty
jraff@brooktrout.com
Intended usage: COMMON
Change controller: Lloyd McIntyre
6. Security Considerations
Security issues for this media type are discussed in the security
considerations section of the media type registration that appears in
section 5.
7. References
[REQ] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[MIME1] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, November 1996.
[MIME4] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part Four: Registration Procedures", BCP
13, RFC 2048, November 1996.
[TIFF] Adobe Developers Association, TIFF (TM) Revision 6.0 -
Final, June 3, 1992.
[TPC.INT] C. Malamud, M. Rose, "Principles of Operation for the
TPC.INT Subdomain: Remote Printing -- Technical
Procedures", RFC 1528, 10/06/1993
[TIFF-FX] McIntyre, L., Zilles, S., Buckley, R., Venable, D.,
Parsons, G. and J. Rafferty, "File Format for Internet
Fax", RFC 2301, January 1998.
Annex A. List of edits to TIFF-FX Registration
+----+---------+-------------------------------------------------+
| No.| Section | Edit Nov. 21, 2000 |
+----+---------+-------------------------------------------------+
| 1. | 7.0 | Corrected Magic Number from 49 49 42 00 hex and |
| | | 4D 4D 00 42 hex to 49 49 2A 00 hex and |
| | | 4D 4D 00 2A hex respectively. |
+----+---------+-------------------------------------------------+
Authors' Addresses
Lloyd McIntyre
Xerox Corporation
3400 Hillview Avenue
Palo Alto, CA 94304
USA
Phone: +1-650 813 6762
Fax: +1-650 813 5850
EMail: lmcintyre@pahv.xerox.com
Glenn W. Parsons
Nortel Networks
P.O. Box 3511, Station C
Ottawa, ON K1Y 4H7
Canada
Phone: +1-613-763-7582
Fax: +1-613-763-2697
EMail: gparsons@nortelnetworks.com
James Rafferty
Brooktrout Technology
410 First Avenue
Needham, MA 02494
USA
Phone: +1-781-433-9462
Fax: +1-781-433-9268
EMail: jraff@brooktrout.com
Full Copyright Statement
Copyright (C) The Internet Society (2002). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
AI ELI5
On this page
§1What is TIFF-FX
TIFF-FX (Tag Image File Format Fax eXtended) is a file format for sending faxes over the Internet. It is defined in RFC 2301, which specifies a TIFF-based structure compatible with the existing ITU-T fax standards for Group 3 black-and-white, grayscale and color facsimile.
TIFF has long been used for storing fax images in applications like store-and-forward messaging systems. TIFF-FX provides a standardized structure optimized for Internet fax transmission and designed for devices with low memory or systems that need to process pages one at a time without loading the entire file.
TIFF-FX is a way to store fax images as computer files. It is based on TIFF, which is already used for pictures, but tweaked specifically to work well with fax machines and the Internet.
§2Features and Capabilities
TIFF-FX can describe many kinds of image data: bilevel (black and white only), grayscale, palette-color, full-color and mixed content images. It includes several compression schemes allowing developers to choose the best trade-off between file size and processing time for their use.
TIFF-FX is designed to be extensible and to evolve gracefully as new needs arise. The format is flexible enough to support existing ITU-T fax recommendations while remaining open to future extensions.
TIFF-FX can store black-and-white faxes, color faxes, or a mix. It has several ways to compress the image to make files smaller, and you can add new features to it later without breaking old programs.
§3MIME Type Registration
This RFC formally registers the MIME media type image/tiff-fx with the IANA. The type refers to TIFF-FX Profiles J, C, L and M encoded image data and any future TIFF-FX extensions, or subsets thereof. The content type may also be used for black-and-white image data encoded using TIFF-FX Profiles S or F.
No required parameters are specified for this MIME type, and no optional parameters are defined. The encoding is binary data, and base64 encoding should be used on transport mechanisms that cannot handle binary data directly. The file extension for TIFF-FX files is .TFX, and the Macintosh file type code is TFX.
The magic numbers for identifying TIFF-FX files are the same as standard TIFF: 49 49 2A 00 hex for little-endian byte order, and 4D 4D 00 2A hex for big-endian byte order. Applications using this media type include imaging, fax, messaging and multimedia systems.
The official name for TIFF-FX in email is image/tiff-fx. When a computer sees that label on a file, it knows the file is a fax image. The file also has a special pattern at the beginning so programs can recognize it even without the email label.
§4Security and Status
TIFF-FX uses a structure that stores image data and attributes describing that image. The fields currently defined in the TIFF-FX specification are descriptive in nature and provide information useful for viewing and rendering images. These fields do not induce particular behavior by the recipient application, so they do not create additional security risks beyond those of handling any image file.
Because TIFF-FX has an extensible structure, it would theoretically be possible for fields to be defined in the future that could induce particular actions, but such processing instructions are inconsistent with the goals of the TIFF-FX specification and are not supported.
RFC 3250 was obsoleted by RFC 3950, which revised the MIME type registration.
TIFF-FX files are just image data and labels. They do not contain instructions that could make your computer do something unexpected. The newer RFC 3950 replaced this one.