Case Study: Implementing the MPEG-4 AS Profile on aMulti-core System on Chip Architecture R92921054 楊峰偉 R92942035 張哲瑜 R92942081 陳 宸
Outline • Introduction • Comparison of MPEG-4 SP & ASP • HiBRID-Soc Multi-core Architecture • HiPAR-DSP • Macroblock processor • Stream processor • Conclusion
Introduction • Dedicated Architecture • Single-purpose • Lower flexibility higher performance • Hybrid Architecture • Programmable CPU + dedicated hardware accelerator • Higher flexibility lower performance • FPGA or DSP • Fully programmable • Slow and only for evaluation
HiPAR-DSP • 16 parallel data paths steered by a single RISC controller in SIMD style • Each data path consists of three VLIW controlled arithmetical units: 16 bit MAC, 32bit ALU, and shift & round units. • External connection can be provided via a modular DMA controller. • A GNU based c/c++ complier is available.
Macroblock processor • Shift with round to 0 / ∞ unsigned, signed • Transform, filter (QMC, deblocking) • Average value with rounding control • Sub-pel motion compensation • Addition of absolute value • Controlled Addition/Subtraction • Dequantization • Permute instruction • Motion compensation, deblocking • Branch on vector status registers • Deblocking mode selection
Stream processor • Application • Audio/Video stream generation and separation • Characteristics in MPEG encoding • Multiplexing of different parts of bitstream • Run-Length coding of DCT coefficients • Variable length coding of coded DCT coefficients (using Huffman table)
Software development environment • Optimizing assemblers are available • Data parallelism via SIMD or subword parallelism • Instruction parallelism via VLIW • Special instruction optimized for video and image processing algorithm
Comparison Between PSoC and HiBRID • PSoC ( Programmable SoC ) • Array of Analog Blocks • Array of Digital Blocks • General Purpose Architecture • HiBRID • More suitable for Multimedia Application • Three cores for different class of functionality
Conclusion • Use the appropriate DSP architecture for different applications. • Multiple codecs can be efficiently implemented on a single platform • Hybrid SoC architecture is the optimal solution for various kinds of video and image applications.
Reference • “The M-PIRE MPEG-4 codec DSP and its macroblock engine,” in Proc. 2000 IEEE Int. Symp. CircuitsSyst., pp. II 192-195. • “HIPAR-DSP 16, A Scalable Highly Parallel DSP Core For System On A Chip Video And Image Processing Applications,” in Proc. 2002 IEEE Int. Conf.Acoust. Speech Signal Processing, May 2002. • ARM Ltd. (1999, May). AMBA Specification Rev. 2.0. [Online]. Available: www.arm.com • “Instruction set extensions for MPEG-4 video” J. VLSI Signal Processing Syst., vol. 23, pp. 27-50,Oct. 1999. • “VLSI Architecture for Mpeg-4” Peter Pirsch, Mladen Berekovic, Hans-Joachim Stolberg, and Jom Jachalsky. • “Open multimedia application platform: enabling multimedia applications in third generation wireless terminals through a combined RISC/DSP architecture” Jamil Chaoui, Ken Cyr, Sebastien de Gregorio, Jean-Pierre Giacalone, Lennifer Webb, Yves Masse. • “HIBRID-SOC: A multi-core architecture for image and video applications” M. Berekovic, S. flugel, H-J. stolberg, L. Friebe, S. Moch, M. B. Kulaczewski, P. pirsch