Feature Extraction of Bisindo Alphabets Using Chain Code Contour

Abstract—This paper proposes a new method of features extraction of BISINDO (Indonesian Sign
Language) alphabet forms. The extracted features play a very important role in the process of hand
pattern recognition which expresses BISINDO alphabets and recognize letters when
communicating. The proposed method consisted of 5 processes; segmentation, morphology closing, edge
detection, contour following, and chain codes formation. 26 hand patterns representing the 26 BISINDO
alphabets from A to Z are used during the experiments. The extracted features of each hand pattern
(each BISINDO alphabet) are presented in terms of the probability value of occurrence of each chain
code direction. The analysis result shows that every hand pattern expressing BISINDO letters has
different features. This indicates that the extracted feature by the proposed method is very accurate to be
used for BISINDO alphabets recognizing based on the hand pattern feature when communicating.
Keyword- Bisindo, Morphology Closing, Edge detection, Contour following, Chain Code