An effective algorithm for centerline extraction and length calculation from human metaphase chromosomes

The study of human metaphase chromosomes is an important feature in diagnosis of genetic disorders. Although many image processing techniques have been developed for chromosomal karyotyping to assist in laboratory diagnosis but they fail to provide reliable results in extracting the centerline of chromosomes due to their shape variability when placed on microscope slides. The technique of arranging the chromosomes according to its length is called karyotyping. The paper proposes an algorithm that uses Discrete Curve Evolution based skeleton pruning and morphological thinning to provide a reliable centerline that is robust to shape variations of the chromosomes. Effective identification of the chromosome outline with its centerline provides a basis for further operations such as homologue chromosome identification, centromere identification etc. Also the length calculation is done by considering the number of white pixels obtained using the thinning algorithm.