Real-time H264/AVC encoder based on enhanced frame level parallelism for smart multicore DSP camera

Nejmeddine Bahri (1) , Nidhameddine Belhadj (1) , Thierry Grandpierre (2) , Mohamed Ali Ben Ayed (1) , Nouri Masmoudi (1) , Mohamed Akil (2)

1 LETI - Laboratoire d'électronique et des technologies de l'Information [Sfax]
2 LIGM - Laboratoire d'Informatique Gaspard-Monge

The latest generation of multicore digital signal processors (DSP), their high computing power, low consumption, and integrated peripherals will allow them to be embedded in the next generation of smart camera. Such DSPs allow designers to evolve the vision landscape and simplify the developer’s tasks to run more complex image and video processing applications without the need to burden a separate personal computer. This paper explains the exploitation of the computing power of a multicore DSP TMS320C6472 to implement a real-time H264/AVC video encoder. This work can be considered as a milestone for the implementation of the new High Efficiency Video Coding standard (HEVC-H265). In fact, to improve the encoding speed, enhanced Frame Level Parallelism (FLP) approach is presented and implemented. A real-time fully functional video demo is given, taken into account video capture and bitstream storage. Experimental results show how we efficiently exploit the potentials and the features of the multicore platform without inducing video quality degradation in terms of PSNR or bitrate increase. The enhanced FLP using five DSP cores achieves a speedup factor of more than four times in average compared to a mono-core implementation for Common Intermediate Format (CIF 352 × 288), Standard Definition (SD 720 × 480), and High Definition (HD 1280 × 720) resolutions. This optimized implementation allows us to meet the real-time compliant by reaching an encoding speed of 99 f/s (frame/second) and 30 f/s for CIF and SD resolutions respectively, and saves up to 77 % of encoding time for HD resolution.

Mots clés: Frame level parallelism; Real-time; AVC; Smart camera; H264; H264/AVC; encoder; Multicore; DSP

Domaines: Traitement du signal et de l'image [eess.SP]

Nejmeddine Bahri, Nidhameddine Belhadj, Thierry Grandpierre, Mohamed Ali Ben Ayed, Nouri Masmoudi, et al.. Real-time H264/AVC encoder based on enhanced frame level parallelism for smart multicore DSP camera. Journal of Real-Time Image Processing, 2014, 12, pp.791-812. ⟨10.1007/s11554-014-0470-6⟩. ⟨hal-01192770⟩