A comparative study on the contour tracking algorithms in ultrasound tongue images with automatic re-initialization

The feasibility of an automatic re-initialization of contour tracking is explored by using an image similarity-based method in the ultrasound tongue sequences. To this end, the re-initialization method was incorporated into current state-of-art tongue tracking algorithms, and a quantitative comparison was made between different algorithms by computing the mean sum of distances errors. The results demonstrate that with automatic re-initialization, the tracking error can be reduced from an average of 5–6 to about 4 pixels, a result obtained by using a large number of hand-labeled frames and similarity measurements to extract the contours, which results in improved performance.