Design of an interface on PDA for Korean

We present an on-line recognition system of cursive Korean character on a PDA. Because of the limited storage capacity and small size of the PDA, a more compact and more convenient design is needed in an embedded user interface, like the on-line character recognition system. To make a convenient interface, the character recognition system has to recognize the cursive type of Korean characters. We define a cursive type of Korean characters as the connection of primitive strokes. We use the path discriminant HMM (PDHMM). The initial structure of the PDHMM is designed from the hand-printed characters and then it is expanded to the cursive case. When new strokes for the cursive type are defined, we can easily extend the PDHMM by inserting proper edges. To save the storage space of the PDA, character recognition is done simply with traversing a single PDHMM. We make smaller states for the PDHMM than the ones for other HMMs. We implemented it on a handheld PC (HPC) and got a good recognition rate.