The Journal of Supercomputing manuscript No. (will be inserted by the editor) Slice-based parallel approach for HEVC encoder P. Pi˜ nol · H. Migall´ on · O. L´ opez-Granado · M.P. Malumbres Received: date / Accepted: date Abstract The HEVC is the very last video coding standard that significantly increases the computing demands to encode video to reach the limits on com- pression efficiency. Our interest is centered on applying parallel processing techniques to HEVC encoder in order to significantly reduce the computational time without disturbing the coding performance behavior. We propose a par- allelization approach to the HEVC encoder which is well suited to multicore architectures. Our proposal uses OpenMP programming paradigm working at slice parallelization level. We encode several slices of each frame at the same time using all available processing cores. The results show that speed-ups up to 9.8 can be obtained for the All Intra mode and up to 8.7 for Low-Delay B, Low-Delay P and Random Access modes with a negligible loss in coding performance. Keywords Parallel algorithms, video coding, HEVC, multicore, performance This research was supported by the Spanish Ministry of Education and Science under grant TIN2011-27543-C03-03, the Spanish Ministry of Science and Innovation under grant TIN2011-26254. P. Pi˜ nol Physics and Computer Architecture Dept. Miguel Hern´andez University, 03202 Elche, Spain. H. Migall´ on Physics and Computer Architecture Dept. Miguel Hern´andez University, 03202 Elche, Spain. Tel.: +34-966658390 Fax: +34-966658814 E-mail: hmigallon@umh.es O. L´ opez-Granado Physics and Computer Architecture Dept. Miguel Hern´andez University, 03202 Elche, Spain. M.P. Malumbres Physics and Computer Architecture Dept. Miguel Hern´andez University, 03202 Elche, Spain.