Dimension Set Recognition Methodologies

Recognition of dimension sets plays an important role in computerizing paper-based engineering drawings. The dimensioning mechanism and its geometric properties have been extensively studied in the past, based on which various techniques have been developed in respect to dimension text and graphics separation, and dimension graphics recognition. This paper reviews the methodologies of automatically recognizing dimension sets in an engineering drawing. Related computerization processes are backgrounded. The elements and classification of a dimension set are described by means of its syntax and semantics. The algorithms for dimension text extraction, dimension graphics recognition and text-graphics aggregation are presented in detail. Some unsolved issues are also addressed. The review is focused on recent research results in the pertinent areas.