INTERNATIONAL  TELECOMMUNICATION  UNION	

CCITT	T.503
THE  INTERNATIONAL
TELEGRAPH  AND  TELEPHONE
CONSULTATIVE  COMMITTEE

TERMINAL  EQUIPMENT  AND  PROTOCOLS
FOR  TELEMATIC  SERVICES

A  DOCUMENT  APPLICATION  PROFILE
FOR  THE  INTERCHANGE
OF  GROUP  4  FACSIMILE  DOCUMENTS

Recommendation  T.503

	Geneva, 1991	

FOREWORD
	The CCITT (the International Telegraph and Telephone Consultative Committee) is a permanent organ of the International Telecommunication Union (ITU). CCITT is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis.
	The Plenary Assembly of CCITT which meets every four years, establishes the topics for study and approves Recommendations prepared by its Study Groups. The approval of Recommendations by the members of CCITT between Plenary Assemblies is covered by the procedure laid down in CCITT Resolution No. 2 (Melbourne, 1988).
	Recommendation T.503 was prepared by Study Group VIII and was approved under the Resolution No. 2 procedure on the 18 of January 1991.

___________________

CCITT  NOTE
	In this Recommendation, the expression "Administration" is used for conciseness to indicate both a telecommunication Administration and a recognized private operating agency.

ã  ITU  1991
All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU.

PAGE BLANCHE

Recommendation T.503
Recommendation T.503
A  DOCUMENT  APPLICATION  PROFILE  FOR  THE  INTERCHANGE
OF  GROUP  4  FACSIMILE  DOCUMENTS

(revised 1990)

CONTENTS
1	Scope
2	Field of application
3	References
4	Definitions
5	Characteristics supported by this document application profile
	5.1	Overview
	5.2	Logical characteristics
	5.3	Layout characteristics
	5.4	Content characteristics
6	Definition of the document application profile
	6.1	Overview
	6.2	Definition of document structure
	6.3	Definition of attribute values
	6.4	Content architectures
Annex A — Format of the values of the attributes “object identifier”.
1	Scope
1.1	This Recommendation defines a document application profile conforming to the T.410 series of Recommendations
	Its purpose is to specify an interchange format suitable for the interchange of Group 4 facsimile documents that contain only raster graphics.
	Documents are interchanged in a formatted form, which enables the recipient to display or print the document as intended by the originator.
1.2	This Recommendation, together with designated parts of T.563, defines a document application profile that may be used by any telematic service.
2	Field of application
2.1	This Recommendation defines a document application profile that is in conformance with T.410 Series of Recommendations and that allows Group 4 facsimile documents to be interchanged only in a formatted form, which allows a recipient to reproduce the document as intended by the originator.

2.2	This document application profile is designed to be independent of the means used to create or to interchange the encoded documents.
2.3	The features which can be interchanged used this document application profile fall into the following categories:
a)	Page format features — these concern how the layout of each page of a document will appear when reproduced;
b)	Raster-graphics layout and imaging features — these concern how the document content will appear within the pages of the reproduced document;
c)	Raster-graphics coding — these concern the raster graphics representations and control functions that make up the document raster-graphics content.
2.4	It is assumed that, when negotiation is performed by the service using this document application profile, all non-basic features are subject to negotiation.
3	References
	The following references are required in order to implement this Recommendation:
—	T.410 series: “Open Document Architecture (ODA) and Interchange Format”.
—	Rec. T.6: “Facsimile Coding Schemes and Coding Control Functions for Group 4 facsimile apparatus”.
—	Rec. X.208: “Specification of Abstract Syntax Notation One”.
—	Rec. X.209: “Basic Encoding Rules for Abstract Syntax Notation One”.
—	Rec. T.417: “ODA Raster Graphics Content Arthitectures”.
—	Rec. T.563: “Terminal Characteristics for Group 4 Facsimile Apparatus”.
4	Definitions
	The definitions in Recommendation T.411 apply to this Recommendation.
5	Characteristics supported by this document application profile
5.1	Overview
	A Group 4 facsimile document is the result of a formatting process and therefore the purpose of this document application profile is to allow transfer of the complete layout of the document.
	Only one category of content is allowed within the same page, namely: raster graphics content (per CCITT Recommendation T.417) as used by facsimile Group 4 apparatus.
	This section specifies the functional description of the features supported by this document application profile.
5.2	Logical characteristics
	Not applicable.

5.3	Layout characteristics
5.3.1	Layout document structure
	A document is seen as a succession of pages.
	The content of a page is: raster graphics content architecture.
5.3.2	Document structure elements
5.3.2.1	Page format
5.3.2.1.1	The document is imaged in a text area which must be within the assured reproduction area.
5.3.2.1.2	The dimensions of the assured reproduction area depend on the paper used.
5.3.2.1.3	The possible paper formats are defined in Recommendation T.563.
5.3.2.1.4	Only the vertical orientation of the page is permitted.
5.3.2.2	Block
	Not applicable (the content is directly related to the page).
5.4	Content characteristics
	The Group 4 facsimile document contains raster graphics in facsimile Group 4 format.
5.4.1	Raster-graphics content
5.4.1.1	Raster-graphics imaging
	The content of raster-graphics is defined by the dimensions of the page and the number of pels per line, in accordance with Table 2/T.563.
5.4.1.2	Pel spacing, line spacing and pel transmission density
	This property defines the distance between successive pels on a line and between successive lines of pels.
	The basic value is 6 BMU, corresponding to 200 pels per 25.4 mm. It is also the default value.
	The non-basic values are 3, 4 and 5 BMU, respectively corresponding to 400, 300 and 240 pels per 25.4 mm.
5.4.2	Received document
	This document application profile, being limited to formatted form, does not support any features to facilitate processing of an interchanged document by a receiver.
6	Definition of the document application profile
6.1	Overview
6.1.1	Document architecture level
	This document profile makes use of document architecture class FDA, as defined in Recommendation T.412. A document according to this document architecture profile includes a specific layout structure only.

	The document architecture level is defined in Tables 2/T.503, 3/T.503 and 4/T.503.
	The specific layout structure is always present in any document conforming to this document application profile.
6.1.2	Content architecture level
	The content architecture level that may be used in documents conforming to this document application profile is as follows: raster graphics formatted content architecture level, defined in Tables 5/T.503 and 6/T.503.
	The coding method to be used is that defined by Recommendation T.6. In addition, any non-basic features defined in Recommendation T.6 may be used, provided that they are indicated in the document profile.
6.1.3	Document profile level
	The document profile level used in this document application profile is defined in Table 1/T.503. Every document interchanged in accordance with this document application profile must include a document profile. Every non-basic attribute value used in a document must be indicated in the document profile.
6.1.4	Interchange format class
	The interchange format class used in this document application profile is “B”, as defined in Recommendation T.415.
6.2	Definition of document structure
6.2.1	Specific layout structure
	The number of hierarchical levels is 2, namely:
—	document layout root;
—	page.
	The document layout root and page levels are mandatory. Only one content portion must be associated with each page.
6.2.2	Generic layout structure
	Not applicable.
6.3	Definition of attribute values
	The attributes applicable to layout components are defined in Table 2/T.503. The following notation is used in this table:
- - -		attribute not applicable to object description
m		mandatory attribute
nm		non-mandatory attribute
d		defaultable attribute.
	Capital letters (M, NM and D) are used for groups of attributes. The allowable attribute values for object descriptions are defined in Table 3/T.503.
TABLE 1/T.503
Document profile attributes
Attribute	Value	Permissible values	
Document profile descriptor	M		
	Specific layout structure	m	Present	
	Document characteristics	M		
		Document Application Profile	m	Group 4 fax	
		Document architecture class	m	Formatted	
		No basic document charact.	NM		
			Page dimensions
			   (see Note 1)	nm	North American letter = (10 200, 13 200 fixed or variable)
ISO B4 = (11 811, 16 677 fixed or variable)
ISO B3 = (14 030, 19 840 fixed or variable)
Japanese legal  = (12 141, 17 196 fixed or variable)
Japanese letter = (8598, 12 141 fixed or variable)
North American legal = (10 200, 16 800 fixed or variable)
North American ledger = (13 200, 20 400 fixe or variable)
(see Note 2)	
			Raster graphics coding attributes	NM		
			Compresion	nm	Uncompressed	
			Raster graphics presentation features	NM		
			Pel transmission density	nm	5 BMU (240 pels/25.4 mm)
4 BMU (300 pels/25.4 mm)
3 BMU (400 pels/25.4 mm)	
Note 1 — This dimension attribute is represented as a data element which consists of two integers.
Two integers specify width and height of a page in basic measurement units (BMUs).
Note 2 — An indefinite page length is represented by a variable measure in the vertical dimension. The value of this data is then arbitrary and should be the nominal page length.			

TABLE 2/T.503
Attributes applicable to layout components

Attribute	Document
layout
root	
Page	
Shared attributes			
	Object type	m	m	
	Object identifier	nm	nm	
	Subordinate	nm	- - -	
	Content portions	- - -	nm	
	Default value lists	nm	- - -	
Layout attributes			
	Presentation attributes	- - -	d	
	Dimensions	- - -	d	

TABLE 3/T.503
Attribute values for layout objet descriptions
Attribute	Basic value	Default value	Non-basic value	
Shared attributes				
	Object type	Document layout root,
page	None	None	
	Object identifier	As defined in Rec. T.412
(see also Annex A)	None	None	
	Subordinate	As defined in Rec. T.412	None	None	
	Content portions	As defined in Rec. T.412	None	None	
	Default value lists	See Table 4/T.503	None	None	
Layout attributes				
	Presentation attributes	See Table 5/T.503			
	Dimensions
	(see Note 1)	Horizontal = 9920 BMU	Horizontal = 9920 BMU	North American letter
	= (10 200, 13 200)
ISO B4 = (11 811, 16 677)	
	Vertical = 14030 BMU
(see Note 2)	Vertical = 14 030 BMU
(see Note 3)	ISO A3 = (1430, 19 840)
Japanese legal
	= (12 141, 17 196)
Japanese letter
	= (8598, 12 141)
North American legal
	= (10 200, 16 800)
North American ledger
	= (13 200, 20 400)
(see Note 2)	
Note 1 — This dimension attribute is represented as a date element which consists of two integers. Two integers specify width and height of a page in basic measurement units (BMUs).
Note 2 — Width is indicated by fixed measure, and at the same time height is indicated by either fixed or variable measure.
The use of variable measure for height indication depends o each application, for example, real time scanning, fixed printing paper, etc. Therefore, for example, when a transmitting terminal requests to use variable measure for height indication, a receiving terminal will accept variable measure for height indication even though the receiving terminal adopts cut sheet paper (fixed size paper) for printing.
Note 3 — Both width and height are indicated by fixed measures.				

TABLE 4/T.503
Defaultable attributes that may be specified
in a default value list of the document layout root
Object type	Defaultable attributes
that can be specified	
Page	Presentation attributes
Dimensions	

6.4	Content architectures
	The following raster graphics content architecture level is used in this document application profile.
6.4.1	Raster graphics content architecture level
	The type of coding to be used is as defined in Recommendation T.6.
	The code extension control function may be used, provided its use is agreed by prior negotiation and is indicated in the document profile. This control function is used to invoke uncompressed mode of coding.
	The presentation attributes that may be used are defined in Table 5/T.503.
TABLE 5/T.503
Presentation attributes
Attributes	Basic values	Default values	Non-basic values	
Type de contenu	Formatted raster graphics
content architecture	Formatted raster graphics
content architecture	None	
Raster graphics attributes				
	Pel path	0°	0°	None	
	Line progression	270°	270°	None	
	Pel transmission density	6 BMU
(200 pels/25.4 mm)	6 BMU	5 BMU (240 pels/25.4 mm)
4 BMU (300 pels/25.4 mm)
3 BMU (400 pels/25.4 mm)	

6.4.2	Coding attributes
	Attributes applicable to content portions are defined in Table 6/T.503.
TABLE 6/T.503
Attributes applicable to content portions
Attributes	Qualifier	Basic values	Default value	Non-basic values	
Content identifier layout	nm	As defined in
Rec. T.412	None	None	
Type of coding	d	T.6	T.6	None	
Raster graphics coding attributes					
	Number of pels per line	d	As defined in
Table 3/T.563	As defined in
Table 3/T.563	None	
	Compression	d	Compressed	Compressed	Uncompressed	
	Number of discarded pels	d	As defined in
Table 3/T.563	As defined in
Table 3/T.563	None	
	Content information	m	T.6 string	None	None	

ANNEX A
(to Recommendation T.503)
Format of the values of the attributes “object identifier”
	The object identifiers of the specific layout object descriptions are composed of sequences of numbers, each of these numbers representing a particular level of the specific layout structure.
	The number assigned to the specific document layout root object description is “1”. The subordinate pages ave a second number which uniquely identifies a particular page. The delimiter between “1” and this second number is the “space” character.
	Example:
	“1 27”	corresponding coding: '31 20 32 37'H
	where character '1' is coded 03/01 or 31 in hexadecimal,
 	where character 'space' is coded 02/00 or 20 in hexadecimal,
	where character '2' is coded 03/02 or 32 in hexadecimal,
	and where character '7' is coded 03/07 or 37 in hexadecimal.
	Content portion identifiers are composed of the identifier of the page to which the content portion belongs and an additional number which identifies the content portion.
	Examples:
	page description	“1 27”	 coding: '31203237'H
	content portion associated with the page	“1 27 1”	 coding: '312032372031'H (optional).
	The value of the attribute “content portions” consists of a single number, which indicates the content portion of that object. This number is equal to the last number in the content portion identifier.