The use of parallel computing with the AMD graphics processors for the construction of displacement vector fields
The aim of the study is to develop a parallel algorithm for constructing displacement vector fields based on recursive search approach with the use of parallel computing at GPU and estimation of time costs. A modified algorithm for the displacement estimation DRS (direct recursive search) was implemented beingand based on the approach to three-dimensional recursive search (3DRS). By considering the DRS features and limitations for the hardware parallel computing, the parallel algorithm PDRS for constructing displacement vector fields has been developed. The latter employs recursive search, which was implemented with the use of the OpenCL programming language to run onto GPUs AMD Radeon. Test results showedhave shown that the use of graphics processors can significantly reduce the time of construction of displacement vector fields. Processing time at preset parameters and images with a resolution of 3456 × 5184 was decreasing by ~ 27 times. When the density of the vector field was increased by three times (spacing between vectors was equal to 16 pixels) as well as the number of vectors in the lines the time required for implementing the parallel algorithm PDRS was 63 times less as compared to the DRS algorithm, realized withwhich was implemented using the high level language C++ for the CPU operation by CPU. This is related to the fact that with increasing the size of the vectors in the line the program uses a larger number of cores in parallel graphics method for constructing vectors in a row as the size of the vectors in the line increases. The vector operations were applied to compute the similarity measure SAD. Their employment incorporation allows reducing the computation time by 1.5-2 times at use offor AMD Radeon 5570 and 7970 graphical cards. In contrast with, the current implementation being realized with, which uses the PDRS algorithm that employs vector operations on the previous generation graphics card Radeon 5570 a previous generation one shows a has shown greater effect of reducing the computation time. The reason is associated with the differences between the architecture of those two video processors.