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 <[email protected]>.




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RFC 3250                     image/tiff-fx                September 2002


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.









McIntyre, et. al.           Standards Track                     [Page 2]

RFC 3250                     image/tiff-fx                September 2002


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: [email protected]
  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.





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RFC 3250                     image/tiff-fx                September 2002


  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
     [email protected]

     Glenn W. Parsons
     [email protected]

     James Rafferty
     [email protected]

  Intended usage: COMMON

  Change controller: Lloyd McIntyre









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RFC 3250                     image/tiff-fx                September 2002


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.






















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RFC 3250                     image/tiff-fx                September 2002


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: [email protected]


  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: [email protected]


  James Rafferty
  Brooktrout Technology
  410 First Avenue
  Needham, MA  02494
  USA

  Phone: +1-781-433-9462
  Fax:   +1-781-433-9268
  EMail: [email protected]








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RFC 3250                     image/tiff-fx                September 2002


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.



















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