Efficient GPU-accelerated parallel cross-correlation

Cross-correlation is a data analysis method widely employed in various signal processing and similarity-search applications. Our objective is to design a highly optimized GPU-accelerated implementation that will speed up the applications and also improve energy efficiency since GPUs are more efficient than CPUs in data-parallel tasks. There are two rudimentary ways to compute cross-correlation - a definition-based algorithm that tries all possible overlaps and an algorithm based on the Fourier transform, which is much more complex but has better asymptotical time complexity. We have focused mainly on the definition-based approach which is better suited for smaller input data and we have implemented multiple CUDA-enabled algorithms with multiple optimization options. The algorithms were evaluated on various scenarios, including the most typical types of multi-signal correlations, and we provide empirically verified optimal solutions for each of the studied scenarios.