DEFORMATION ANALYSIS OF THE VOCAL FOLDS FROM VIDEOSTROBOSCOPIC IMAGE SEQUENCES OF THE LARYNX

Videostroboscopy is an examination which yields a permanent record of the moving vocal folds. Thus, it allows the diagnosis of abnormalities which contribute to voice disorders. In this paper, in order to find and quantify the deformation of the vocal folds in videostroboscopic r ecordings, an active contours-(snakes) based approach is used to delin eate the vocal folds in each frame of the videostroboscopic image sequ ence. After this delineation, a new elastic registration algorithm is used to register the vocal fold contours between adjacent frames of th e video sequence. This algorithm is based on the regularization princi ple and is very effective when large deformations are present. A least -squares approach is used to fit an affine model to the displacement v ectors found by elastic registration. The parameters of this model, ro tation, translation, and deformation along two principle axes, quantif y the deformation and allow the succinct characterization of the video stroboscopic recordings based on the deformations that occurred: Exper iments are shown with synthetic and real videostroboscopic data that d emonstrate the value of the proposed approach. (C) 1998 Acoustical Soc iety of America.