Document image understanding: integrating recovery and interpretation
David Doermann · 1993
Many document image understanding problems require a more comprehensive examination of document features than is typically deemed necessary for recognition tasks. We believe that these problems require a detailed analysis of and sub-stroke features in the document image with the goal of obtaining information about the environment or process which created the document and establishing a context for understanding. We introduce the concept of recovery into the document domain. We provide a stroke representation which establishes a verifiable link to the pixels and demonstrate its usefulness for recovery tasks. This representation allows us to overcome many of the problems associated with the rapid, irreversible abstraction associated with traditional document processing methods and provides the basic framework for our analysis of handwritten documents. By obtaining a detailed description of the document and its properties, we are able to establish a context for analysis and validate assumptions about the domain. This dissertation presents our work on several document image understanding problems: (1) demonstrating the successful use of the platform for the problem of interpreting and reconstructing junctions and endpoints, (2) exploring the effects of the handwriting process on the document by the development of a model for instrument grasp and a study of its effects on pressure features, (3) posing and providing an approach to the problem of recovering temporal information from static images of handwriting, (4) addressing various sub-tasks of the problem of processing form documents, and (5) extending the detailed analysis philosophy to demonstrate its feasibility in related document domains.