RFC 2306 (rfc2306) - Page 2 of 25
Tag Image File Format (TIFF) - F Profile for Facsimile
Alternative Format: Original Text Document
RFC 2306 TIFF-F Profile March 1998
2.1 Baseline TIFF and Applications
TIFF provides a method to describe and store raster image data. A
primary goal of TIFF is to provide a rich environment within which
implementations can exchange image data. [TIFF] characterizes
Baseline TIFF as being the core of TIFF, the essentials that all
mainstream TIFF developers should support in their products.
Applications of TIFF are defined by using Baseline TIFF as a starting
point and then defining "extensions" to TIFF that are used for the
specific "application", as well as specifying any other differences
from Baseline TIFF.
3. TIFF-F Definition
3.1 Introduction
Though it has been in common usage for many years, TIFF-F has
previously never been documented in the form of a standard. An
informal TIFF-F document was originally created by a small group of
fax experts led by Joe Campbell. The existence of TIFF-F is noted in
[TIFF] but it is not defined. This document defines the F
application of [TIFF]. For ease of reference, the term TIFF-F will be
used throughout this document as a shorthand for "F Profile of TIFF
for Facsimile". TIFF-F files are intended for use with the
image/tiff MIME media content-type which includes support for the
"application" parameter (e.g., application=faxbw).
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 [REQ].
3.1.1 TIFF-F Historical Background
Up until TIFF 6.0, TIFF supported various "Classes" which defined the
use of TIFF for various applications. Classes were used to support
specific applications and in this spirit, TIFF-F has been known
historically as "TIFF Class F". Previous informal TIFF-F documents
used the "Class F" terminology.
As of TIFF 6.0 [TIFF], the TIFF Class concept has been eliminated in
favor of the concept of Baseline TIFF. Therefore, this document
updates the definition of TIFF-F as the F profile of TIFF for
facsimile, by using Baseline TIFF as defined in [TIFF] as the
starting point and then defining the differences from Baseline TIFF
which apply for TIFF-F. In almost all cases, the resulting
definition of TIFF-F fields and values remains consistent with those
used historically in earlier definitions of TIFF Class F. Where some
Parsons & Rafferty Informational