Strain measurement in an ultrasound simulation framework
The study focuses on the improvement of ultrasound simulation and image data generation and the development of an accurate strain measurement algorithm. An ultrasound simulation is developed modeling a two-dimensional ultrasound imaging system and the media of scatterers. The time domain point spread function that is used to model the imaging system is based on a novel spatial impulse algorithm. The spatial impulse response and the point spread function are parallel algorithms and their computation runs on GPUs. The ultrasound simulation results are generated for an object under stress. A strain measurement algorithm to track clusters of speckles is developed. Following the Lagrangian approach, this algorithm computes the transformation matrix between the initial and deformed states, and it is based on the statistical relation between the coordinates of speckles of each frame rather than the displacement measurement of a small number of speckles in a region of interest using correlation. Because the algorithm does not depend on searching the pattern in the next image of the sequence, larger deformation quantities can be measured accurately.