Ligature Segmentation Approach for Urdu Handwritten Text Documents
Subhash Panwar, Musthaq Ahamed, Neeta Nain · 2014
Urdu handwritten Document segmentation can be defined as the process of splitting the images of handwritten text document into pieces corresponding to lines, words or ligatures and character. This is a very challenging task because in Urdu handwritten documents, skewed text lines appear frequently with multiple angles. After segmentation of ligature or stroke, also defined as connected components in handwritten text document, we have to sequence the ligatures as appearing in the document so that the meaning of the document is preserved. In this paper, We use bottom up grouping approach for the segmentation. We have used a novel connectivity strength parameter with depth first search approach for extraction of connected components of the same line from complete connected components of the given cursive text document. The exact sequence of connected components is stored in the sequential vector which contains the label of the connected components. The proposed urdu ligature segmentation technique is implemented and tested on various in house generated database having different skewed and curved documents. Quantitative analysis also shows that this approach gives better results and overcomes the problems encountered in Hill-and dale writing styles.