Performance Analysis of DIRAC PRO with H.264 Intra frame coding Presented by Poonam Kharwandikar Guided by Prof. K. R. Rao
What is Dirac? Hybrid motion-compensated video codec developed by BBC. Uses modern techniques - wavelet transforms, arithmetic coding. Open technology no license fees. Easily recreated for new platforms. Applications - HDTV to web streaming.
DIRAC Open technology - no licensing costs. Flexible, ease of operation over many applications. Capable of compressing high resolution files. More freedom for future implementations, more scope to improve performance Comparable to other codecs despite simple toolset. Relative simplicity and clean architecture supports high performance. Good quality at low bit rates, lower costs.
Dirac - Architecture
Dirac - Wavelet Transform o More efficient than block transforms with still images. o Operates on entire picture. o Repeated filtering of signals into low- and highfrequency parts. o Horizontal and vertical filtering for 2D signals. o Logarithmic frequency decomposition into subbands at each stage.
Wavelet Transform contd.. Packs most information into low frequency sub-bands - compression achieved. Process repeated to achieve higher levels of wavelet transform. Coded picture free from block artifacts, superior moving images.
Wavelet Transform contd..
Stages of a wavelet transform
Intra & Inter prediction Three types of frames : I (Intra), L1 (Level 1) and L2 (Level 2). Intra frames - coded without reference. Inter frames - L1, L2 frames coded with reference to previously coded frames. L1 frames used as temporal references for other frames, L2 frames are not. Each frame predicted from up to two reference frames.
History of H.264 History of H.264 / MPEG-4 part 10 ITU-T Q.6/SG16 started work on H.26L (L: Long Range) July 2001: H.26L demonstrated at MPEG (Moving Picture Experts Group) call for technology December 2001: ITU-T VCEG (Video Coding Experts Group) and ISO/IEC MPEG started a joint project Joint Video Team (JVT) May 2003: Final approval from ISO/IEC and ITU-T The standard is named H.264 by ITU-T and MPEG-4 part 10 by ISO/IEC Fidelity Range Extensions (August 2004) Amendment 1 Transport of MPEG-4 AVC on MPEG-2 TS Amendment 3
Purpose of H.264 Higher coding efficiency than previous standards, MPEG-1,2,4 part 2, H.261, H.263 Simple syntax specifications Seamless integration of video coding into all current protocols More error robustness Various applications like video broadcasting, video streaming, video conferencing, D-Cinema, HDTV Network friendliness Balance between coding efficiency, implementation complexity and cost - based on state-of the-art in VLSI design technology
H.264/MPEG-4 AVC architecture
Specific coding parts for the Profiles
Profiles and Levels for particular applications Profile : The standard defines various sets of capabilities which are referred to as Profile Four profiles : Baseline, Main, Extended and High Profile Applications Baseline Main Extended High Video Conferencing Mobil Applications Digital Storage Media Television Broadcasting Streaming Video Content contribution Content distribution Studio editing Post processing
MSE PSNR highway_qcif Bit Rate Vs PSNR 50 40 30 20 H.264 DiracPRO 10 0 54.46 164.06 576.41 BitRate Bit Rate Vs MSE 70 60 50 40 30 20 10 H.264 Dirac PRO 0 54.46 164.06 576.41 BitRate
SSIM highway_qcif Bit Rate Vs SSIM 1 0.95 0.9 0.85 0.8 0.75 H.264 Dirac- PRO 0.7 54.46 164.06 576.41 BitRate
MSE PSNR coastguard_qcif Bit Rate Vs PSNR 50 40 30 20 10 H.264 Dirac- PRO 0 91.21 348.43 943.25 Bit Rate Bit Rate Vs MSE 160 140 120 100 80 60 40 20 0 91.21 348.43 943.25 Bit Rate H.264 Dirac- PRO
SSIM coastguard_qcif Bit Rate Vs SSIM 1.2 1 0.8 0.6 0.4 0.2 0 91.21 348.43 943.25 Bit Rate H.264 Dirac-
MSE PSNR highway_cif Bit Rate Vs PSNR 50 40 30 20 10 0 146.57 427.29 1846.8 Bit Rate H.264 Dirac- PRO Bit Rate Vs MSE 50 40 30 20 10 0 146.57 427.29 1846.8 Bit Rate H.264 Dirac- PRO
SSIM highway_cif Bit Rate Vs SSIM 0.98 0.96 0.94 0.92 0.9 0.88 0.86 0.84 0.82 146.57 427.29 1846.8 H.264 Dirac- PRO Bit Rate
Conclusion As Dirac Pro is royalty free software the H.464 Intra frame and Dirac Pro has comparable results.
References [1] The Dirac web page : http://dirac.sourceforge.net [2] Dirac Pro to bolster BBC HD links : http://www.broadcastnow.co.uk/news/multi-platform/news/diracpro-to-bolster-bbc-hd-links/1732462.article [3] And now, Dirac from the Olympics, a new free codec! http://www.videsignline.com/210601739 [4] What is Dirac Pro : http://www.bbc.co.uk/rd/projects/dirac/diracpro.shtml [5] Dirac codec : http://en.wikipedia.org/wiki/dirac_(codec) [6] K. Onthriar, K. K. Loo and Z. Xue, Performance comparison of emerging Dirac video codec with H.264/AVC, IEEE International Conference on Digital Telecommunications, 2006, ICDT apos; Vol. 06, Page: 22, Issue: 29-31, Aug. 2006. [7] [28] K. Onthriar, K. K. Loo and Z. Xue, Performance comparison of emerging Dirac video codec with H.264/AVC, IEEE International Conference on Digital Telecommunications, 2006, ICDT apos; Vol. 06, Page: 22, Issue: 29-31, Aug. 2006. [8] T. Borer, and T. Davies, Dirac video compression using open technology, BBC EBU Technical Review, July 2005. [9] K. Onthriar, K. K. Loo and Z. Xue, Performance comparison of emerging Dirac video codec with H.264/AVC, IEEE International Conference on Digital Telecommunications, 2006, ICDT apos; Vol. 06, Page: 22, Issue: 29-31, Aug. 2006. [10] H. Eeckhaut, et al, Speeding up Dirac s entropy coder, Proc. 5th WSEAS Int. Conf. on Multimedia, Internet and Video Technologies, pp. 120-125, Greece, Aug. 2005.
References [11]T.Davies, TheDiracAlgorithm :http://dirac.sourceforge.net/documentation/algorithm/, 2005. [12] /CMPT 365 Course Slides/, School of Computing Science, Simon Fraser University,fig3: http://www.cs.sfu.ca/coursecentral/365/li/material/notes/chap4/chap4.3/chap4.3.html [13] T. Davies, A modified rate-distortion optimization strategy for hybrid wavelet video coding, IEEE International Conference on Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings. 2006, Vol.: 2, pp.: II, Publication Date: 14-19 May 2006. [14] H. Eeckhaut, et al, Speeding up Dirac s entropy coder, Proc. 5th WSEAS Int. Conf. on Multimedia, Internet and Video Technologies, pp. 120-125, Greece, Aug. 2005. [15] M. Tun and W. A. C. Fernando, An error-resilient algorithm based on partitioning of the wavelet transform coefficients for a DIRAC video codec, Tenth International Conference on Information Visualization, 2006, IV, Vol. 5-7, pp.: 615 620, Issue : July 2006. [16] H.264/MPEG-4 AVC: http://en.wikipedia.org/wiki/h.264 [17] 4. ITU-T Recommendation H.264 Advanced Video Coding for Generic Audio-Visual services [18] Soon-kak Kwon et al. Overview of H.264 / MPEG-4 Part 10 (pp.186-216), Special issue on Emerging H.264/AVC video coding standard, J. Visual Communication and Image Representation, vol.17, pp.183-552, April 2006. [19] I. Richardson, V-Codex, White Paper - H.264 / MPEG-4 Part 10: Inter Prediction, 2007,www.vcodex.com. [20] S.K. Kwon, A. Tamhankar and K.R. Rao Overview of H.264 / MPEG-4 Part 10 J. VCIR, Vol. 17, pp. 186-216, April 2006, Special Issue on "Emerging H.264/AVC Video Coding Standard," [21] JVT Draft ITU-T recommendation and final draft international standard of joint video specification (ITU-T rec. H.264 ISO/IEC 14496-10 AVC), March 2003, JVT-G050 available on http://ip.hhi.de/imagecom_g1/assets/pdfs/jvt-g050.pdf.