Implementation Guide for Document Style Processing

Introduction

The requirements for "Implementation Guide for Document Style Processing" were proposed in the DocSII (Asian Document Style Standardization for Information Interchange) Symposium 2003, which was held in Ulaan Baatar, Mongolia, Sept 30 and Oct. 1, 2003. Working drafts of the Implementation Guide are reviewed and discussed by the members of DocSII.

1. Document processing model

Logical structured documents, e.g., XML documents, consist of logical elements and their structure description. A style specification for the logical documents indicates style attributes for the logical elements and some structure conversions. Document formatting and rendering is a processing of a mathematical convention that shows a mapping of logical elements onto a physical representation media in accordance with corresponding style specification. Those document processings are illustrated in Figure 1.

Figure 1.1 — Document processing model

When the restriction of style specification is too severe, the mathematical convention will have no solution. To avoid those situations without solution of formatting, the following approaches have been employed:

• a) Some reconciliation rules are applied.
• b) Some style specifications are relaxed and some incorporated in formatting and rendering systems.

NOTE 1: Line-end and page-end processing rules have been usually incorporated in actual formatting and rendering systems. When those formatting and rendering systems are assumed, external style specifications include no specification for line-end and page-end processing rules. Assuming those formatting and rendering systems, the ISO/IEC TR 19758 (DSSSL library for style specification) and its amendments deal with no style library for line-end and page-end processing rules.

The approach b) will cause a slight difference between the rendered page images of sending system and receiving system. To minimize the difference, Implementation Guide for Document Style Processing becomes essential.

2. Scope

This guideline shows some specifications that should be supported by formatting and rendering systems. A negotiation of those specifications between formatting and rendering systems will contribute to preserve page images of documents interchanged between the systems.

3. References

ISO/IEC TR 19758:2003, DSSSL library for complex compositions, 2003-04

4. Terms and definitions

For the purpose of this document, the following terms and definitions apply.

4.1 ***

TBD

5. Line-end processing

5.1 Japanese text

5.1.1 Line head wrap

The characters shown in Figure 5.1 should not be located at the beginning of a line.

Figure 5.1 — Line-head-wrap characters

The possible character should be composed

• at the end of the previous line, or
• at the second character position of the line, adjusting the end character of the previous line to the beginning of this line.

5.1.2 Line end wrap

The characters shown in Figure 5.2 should not be located at the end of a line.

Figure 5.2 — Line-end-wrap characters

The possible character should be composed

• at the beginning of the next line, or
• at the second character position from the end of the line, adjusting the beginning character of the next line to the end of this line.

5.2 Thai text

TBD

6. Page-end processing

6.1 Japanese text

TBD

6.2 Thai text

TBD

7. Number representation

7.1 Conversion between vertical and horizontal compositions in Japan's texts

7.2 ***

8. ***

9. ***

Annex A Bibliography

The following documents have served as informative references in the preparation of this Implementation Guide.

1) DocSII N37, Summary of DocSII Symposium 2003, 2003-10-01

2) JIS Z 8126:2004, Graphic arts — Glossary — Digital printing terms, 2004-02-20

Annex B *****