Ultrasound despeckling for active contour segmentation

Automatic or semi-automatic gradient based segmentation of ultrasound images is problematic because the inherent nature of ultrasound imaging produces speckle. The main concern of this paper is to remove speckle cause gradients that cannot be attributed to anatomic features. Application of despeckling algorithms attempt to remove or reduce the speckle noise and thus the pixelwise gradients caused by speckle. Yet, the despeckling algorithm should preserve edges and gradients that are due to anatomic features such as the boundaries of organs, differing tissues, etc. This paper proposes the use of the noise enhanced squeeze box filter to despeckle cardiac ultrasound images so that an application of well-know gradient based active contour methods can be used for segmentation.