From handwriting analysis to pen-computer applications

In this paper, pen computing, i.e., the use of computers and applications in which the pen is the main input device, will be described from four different angles. In the first section, a brief overview will be given on the hardware developments in pen systems. After concluding that the technological developments in this area did not lead to the expected user acceptance of pen computing, the reasons underlying this market failure are explored: The second part deals with Pen-User Interfacing (PUI) aspects. Problems of pen-user interface design are described. Existing and new applications are summarized. The third part is concerned with the handwriting process and product. The last part deals with automatic recognition methodologies. Four basic factors determining handwriting variation and variability are identified. A handwriting recognition approach using segmentation into velocity-based strokes is handled in somewhat more detail. A large-scale project (UNIPEN) concerns the benchmarking of the performance of on-line handwriting recognition algorithms which is crucial for the advancement of the state of the art in this area.