Image Registration Based Wide-Field-of-View Method in Ultrasound Imaging
WFOV (wide field of view) imaging mode is designed to provide an ultrasound image over an area much larger than the real-time window normally available. This is achieved by combining a real-time image with the prior static image as the probe is scanned over a region of interest, ideally along a straight line path. The static image is updated and compounded continuously as the real time scanning continues to obtain a panorama image. Here we use image registration techniques to recover the probe motion, thus eliminating the need for the position sensor. The image registration technique we use is a three step process composed of motion estimation of local blocks between successive images, motion vectors correction after the motion estimation, and least-squares optimization to estimate the overall motion between the images. The persistence-based spatial compounding method is used for constructing the final noise-suppressed WFOV image.