Popis: |
Contour tracing is an important pre-processing step in many image-processing applications such as feature recognition, biomedical imaging, security and surveillance. As single-processor architectures reach their performance limits, parallel processing architectures offer energy-efficient and high-performance solutions for real-time applications. Parallel processing architectures are thus used for several real-time image processing applications. Among the several interconnection schemes available, Cayley graph-based interconnections offer easy routing and symmetric implementation capabilities. For parallel processing systems with a Cayley graph-based interconnection scheme, torus, we developed three accelerated algorithms corresponding to three existing families of contour tracing algorithms. We simulated these algorithms on a parallel processing framework to quantify the normalized speed-up possible in any torus-connected parallel processing system. We also compared our best-performing algorithm with the existing parallel processing implementations for Nvidia GPUs. We observed a speed-up of up to 468 times using our algorithms on a parallel processing architecture in comparison to the corresponding algorithm on a single processor architecture. We evaluated a speedup of 194 (and 47) compared to the existing parallel processing contour tracing implementation on Tesla K40c (and Quadro RTX 5000 GPU hardware, respectively). We observe that for torus-connected parallel processing architectures used for image processing, our algorithms can speed up contour tracing without any hardware modification. |