Applied Informatics - Distributed Systems

Projects: Designer, Design by Example
Contact: Prof. Dr. A. Brüggemann-Klein

SGML document grammars concern only the syntax of logically marked-up documents. In our system Designer, we provide structured documents with graphic semantics. More precisely, Designer lets graphic artists write design specifications and then applies them to logically marked-up documents, yielding typeset and laid-out documents on paper. This approach to document design emulates, in the context of electronic publishing, the separation of concerns between authoring, editing, designing, and typesetting that is well-established in the traditional publishing industry.

The system has two components: A design-specification language and a transcription program. The transcription program applies a design specification to a logically marked-up document, resulting in a stream of text and formatting commands that is further processed by the formatter (that is, a typesetting program). Therefore, the transcription program automates the traditional copy editor's task of marking up the manuscript with instructions to the typesetter.

The system is not meant to automatically create well-styled documents, which seems as difficult a task as that of measuring the beauty of artwork. The goal of Designer is to provide a high-level language for professional graphic artists to write down design specifications, and to integrate these design specifications into the electronic publishing process.

In February 1995, DSSSL, the Document Style Semantics and Specification language, has passed it's final vote to become an ISO standard. DSSSL provides a framework for document designers to express design specifications as Scheme programs. Given the short time DSSSL has been in existence as a standard, there are no systems that can process DSSSL specifications yet; nor are there DSSSL-compliant formatters that are able to process the output of a DSSSL system. As part of the Designer project, we are developing a compiler that translates a Designer design specification into a DSSSL STTP process, so that a DSSSL system can act as a transcription program in our model. As a prerequisite, we are implementing the part of the DSSSL standard that concerns STTP processes. This way Designer serves as a declarative front end to DSSSL.

Even with a declarative language like Designer's, writing the design specification for documents of a complex type is a formidable task. Therefore we are investigating whether document design for classes of documents can be supported by a learning component. In this scenario, the graphic artist specifies the layout for a small number of sample documents of a given type; then the system generalizes rules on how any document of the same type is to be formatted. "Design by Example" is based on paradigms and algorithms of computational learning theory and case-based learning.

This project is in part a joint project with Professor Klein and Stefan Wohlfeil, FernUniversität Hagen.