1. IMPLEMENTATION AND PERFORMANCE ANALYSIS of Dirac VIDEO CODING STANDARD AND COMPARISON WITH AVS CHINA Under the guidance of Dr. K R. Rao Electrical Engineering Department The University of Texas at Arlington By Saumya Raval (1000746720) Saumya.raval@mavs.uta.edu Multimedia Processing (EE 5359) Project Proposal

2. Introduction A software or a device that enables video compression and decompression is known as a video codec [1]. The need for video coding standards arose with the increased commercial interest in video communications. Video coding standards Dirac and AVS China are the latest standards adopted by Broadcasting Corporation BBC and China standards organization respectively [2].

3. Dirac [10] Dirac[10] is a video compression system developed by the British Broadcasting Corporation (BBC) utilizing motion compensation and wavelet transforms. Dirac video codec applications span from mobile, internet, Ultra HDTV to film and video production. The Dirac encoder architecture is shown in Figure 2. The decoder shown in Figure 3 performs the inverse operations.

4. Figure 1: Original image (left), Dirac compressed image(right) [10]

5. Figure 2: Dirac encoder block diagram [10]

6. Figure 3: Dirac decoder block diagram [2]

7. AVS China Part 7 [5] AVS video codec is developed by the audio video coding standard working group of China[5]. AVS China comprises of four different profiles namely Jizhun, Jiben, Shenzan and Jiaqiang of which the Jiben profile (basic profile) is defined in AVS Part 7 for mobile applications [5].

8. ProfilesKey applications Jizhun profileTelevision broadcasting, HDTV, etc. Jiben profileMobility applications, etc. Shenzhan profileVideo surveillance, etc. Jiaqiang profileMultimedia entertainment, etc. Table 1: Applications of the various profiles of AVS China [5]

9. Various profiles of AVS China [18] AVS-Video Jizhun profile (base profile) - First profile in the national standard of AVS-Part2 - Focuses on digital video applications like commercial broadcasting and storage media, including high-definition applications. - Preferable for high coding efficiency on video sequences of higher resolutions, at the expense of moderate computational complexity. AVS-video Jiben profile (basic profile) - Mobility video applications featured with smaller picture resolution - Ability on error resilience is needed due to the wireless transporting environment AVS-Shenzhan profile (extended profile) - Solutions of standardizing the video surveillance applications AVS-Jiaqiang profile (enhanced profile) - Movie compression for high-density storage - Relatively higher computational complexity

10. Parts of AVS China [2] 1.System 2.Video 3.Audio 4.Conformance Test 5.Reference software 6.Digital media rights management 7.Mobile video 8.Transmit AVS via IP (Internet protocol) network 9.AVS file format 10.Mobile speech and audio coding

11. Figure 4: AVS China encoder block diagram [6]

12. Figure 6: AVS China decoder block diagram [5]

13. Layered Structure of AVS China [28] Figure 5: Layered data structure [28]

14. Coding tools in AVS China 8x8 Intra Predictions [18] – Decoded information in the current frame as the reference of prediction – Five luminance four chrominance – Four 8x8 luminance blocks can be predicted using one of the five intra-prediction modes – Prediction of the most probable mode is according to the intra- prediction modes of neighboring blocks Figure 7 : Neighbor pixels in luminance intra prediction [18]

15. Five luminance prediction modes are illustrated in Fig. 8. DC mode (mode2), diagonal down left (mode3) mode and diagonal down right mode (mode 4) and a three-tap low-pass filter (1,2,1) Figure 8: Five luminance intra prediction modes [18]

16. Inter prediction [5] – Derived from the decoded frames – Precision of motion vector in inter prediction is up to 1/4 pixel – Sub-pixel interpolation in AVS-video is called as two steps four taps (TSFT) interpolation [27] and three kinds of filters are applied – Filter of (-1, 5, 5, -1) to get the half-pixel reference pixel values as the first step and a filter of (1, 7, 7, 1) is applied for quarter-pixel reference pixel values either horizontally or vertically as the second step – Exception of the second step is that for quarter-pixel reference pixel values of e, g, p, r, a diagonal bilinear filter is used

17. Figure 9: Position of integer pixels, 1/2 pixels and 1/4 pixels [18]

18. Project Objective This project will give an overview of the working, performance and hardware requirements of Dirac and AVS- China codecs. The objective of this project is to analyze the performance of the baseline profiles of the Dirac and AVS China video codecs based on various factors like complexity, video quality, bit rates, compression ratio, etc. Also using sample videos, factors such as PSNR, MSE and SSIM [24] will be derived for two standard formats at various bit rates.

19. Experimental Results for Dirac The software which has been used to perform Dirac is Dirac 1.0.2 [11] obtained from the official Dirac website [11]. Microsoft Visual C++ 2008 express edition [34] has been used to run the code and build the project for the Dirac codec. After building the project, code will generate two application files namely encode.exe and decode.exe. We run these two files using appropriate and necessary parameters and obtain the final result which is a decoded file. The original file and decoded file are than evaluated using MSU video quality measurement tool. The values of PSNR, MSE and SSIM are obtained from it.

20. Original Sequence: akiyo_qcif.yuv (4:2:0 format) [12] Width: 176 Height: 144 Frame rate: 30 frames/sec (fps) Avg. PSNR obtained: 27.39 Avg. SSIM obtained: 0.6806 Avg. MSE obtained: 118.32

21. Fig 10: Original File akiyo_qcif.yuv (4:2:0 format) Fig 11: Output file with Quality Factor = 30

22. MSU Video quality measurement tool [30] Fig 12: Snapshot of MSU tool

23. Proceeding Work Dirac – Perform operation on the given QCIF sequence using different QF values. – Obtain graph for bitrate vs. PSNR, bitrate vs. SSIM and bitrate vs. MSE. – Perform above operations on a CIF sequence and plot graph of above values. AVS-China – Understanding of working of AVS-China. – Understand code and flow of code. – Implement AVS-China for QCIF and CIF format files using different QF values. – Plot graphs for above three values. Compare the performance of Dirac and AVS-China.

24. Abbreviations and Acronyms AVC: Advanced Video Coding AVS: Audio Video Standard CIF: Common Intermediate Format HDTV: High-Definition Television IEC: International Electrotechnical Commission IP: Internet protocol ISO: International Organization for Standardization ITU-T: International Telecommunication Union - Telecommunication Standardization sector MBPAFF: Macro block pair adaptive field frame MSE: Mean Square Error MV: Motion vector PSNR: Peak Signal to Noise ratio QCIF: Quarter Common Intermediate Format QF: Quality Factor SMPTE: Society of Motion Picture and Television Engineers SSIM: Structural Similarity Metric TSFT: two steps four taps

25. References [1] T. Sikora, “Digital video coding standards and their role in video communications”, Signal processing for multimedia, J.S. Byrnes (Ed.), IOS press, pp. 225-251, 1999. [2] K. R. Rao and D. N. Kim, “Current video coding standards: H.264/AVC, Dirac, AVS China and VC-1,” IEEE 42nd southeastern symposium on system theory (SSST), pp. 1-8, March 2010. [3] 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, ICDT 2006, vol. 6, Page: 22, Issue: 29- 31, Aug. 2006. [4] X. F. Wang and D. B. Zhao, “Performance comparison of AVS and H.264/AVC video coding standards,” Journal of computer science and technology, Vol. 21, No. 3, pp.310-314, May 2006. [5] L. Yu, S. Chen and J. Wang, “Overview of AVS video coding standards,” Signal processing: image communication, Vol. 24, Issue 4, pp. 247-262, April 2009. [6] L. Fan et al, “Overview of AVS video standard”, IEEE International conference on multimedia and expo (ICME), Vol. 1, pp. 423 - 426, June 2004. [7] T. Borer and T. Davies, “Dirac video compression using open technology,” BBC EBU technical review, July 2005. [8] T. Borer, “Dirac coding: tutorial and implementation,” EBU networked media exchange seminar, EBU, Geneva, 22-23 June 2009. [9] Dirac specification, Version 2.2.3, Available: http://diracvideo.org/download/specification/dirac-spec-latest.pdfhttp://diracvideo.org/download/specification/dirac-spec-latest.pdf [10] BBC research on Dirac: http://www.bbc.co.uk/rd/projects/dirac/technology.shtmlhttp://www.bbc.co.uk/rd/projects/dirac/technology.shtml [11] Dirac video download source reference: http://diracvideo.org/download/http://diracvideo.org/download/ [12] YUV video sequences source: http://trace.eas.asu.edu/yuv/http://trace.eas.asu.edu/yuv/ [13] Z. Wang, et al, “Image quality assessment: From error visibility to structural similarity”, IEEE Transactions on Image Processing, Vol. 13, No. 4, pp. 600-612, April 2004. [14] A. Ravi and K.R. Rao, “Performance analysis and comparison of the Dirac video codec with H.264/MPEG-4 part 10 AVC”, International journal of wavelets, multi-resolution and information processing, Vol. 09, Issue: 04, pp: 635-757, Jan. 2010. [15] L. Fan, “Mobile multimedia broadcasting standards”, Springer Publication, ISBN 978-0-387-78263-8, 2009. [16] AVS-China official website: http://www.avs.org.cnhttp://www.avs.org.cn

26. [14] A. Ravi's Thesis under Dr. K.R. Rao, “Performance analysis and comparison of the Dirac video codec with H.264/MPEG-4 part 10 AVC”, International journal of wavelets, multi-resolution and information processing, Vol. 09, Issue: 04, pp: 635-757, January 2010. [15] L. Fan, “Mobile multimedia broadcasting standards”, Springer Publication, ISBN 978-0-387-78263-8, 2009. [16] AVS-China official website: http://www.avs.org.cnhttp://www.avs.org.cn [17] Dirac video codec - A programmer's guide: http://dirac.sourceforge.net/documentation/code/programmers_guide/toc.htm [18] L. Yu et al, “Overview of AVS-Video: tools, performance and complexity,” SPIE VCIP, Vol. 5960, pp. 596021- 1~596021-12, Beijing, China, July 2005. [19]Dirac developer support: Wavelet transform: http://dirac.sourceforge.net/documentation/algorithm/algorithm/wlt_transform.xht http://dirac.sourceforge.net/documentation/algorithm/algorithm/wlt_transform.xht [20] T. Davies, “The Dirac algorithm”: http://dirac.sourceforge.net/documentation/algorithm/ [21] H. Eeckhaut, et al, “Speeding up Dirac’s entropy coder”, 5th WSEAS International conference on multimedia, internet and video technologies, pp. 120-125, Greece, Aug. 2005. [22] M. Tun, K. K. Loo and J. Cosmas, “Semi-hierarchical motion estimation for the Dirac video codec”, 2008 IEEE international symposium on broadband multimedia systems and broadcasting, pp. 1-6, 2008. [23] 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. [24] W. Gao et al, “AVS - The Chinese next-generation video coding standard”, NAB, Las Vegas, 2004. [26] Power point slides by L.Yu, chair of AVS video : http://www.ee.uta.edu/dip/Courses/EE5351/ISPACSAVS.pdfhttp://www.ee.uta.edu/dip/Courses/EE5351/ISPACSAVS.pdf [27] R. Wang, et al., “Sub-pixel motion compensation interpolation filter in AVS”, 2004 IEEE International Conference on Multimedia and Expo, pp. 93-96, 2004. [28] Project proposal on "Low Complexity AVS-China Part-2 video using data mining techniques" by Jennie Abraham: http://www-ee.uta.edu/Dip/Courses/EE5359/Thesis%20Project%20table%20docs/ jennieproposal.doc [29] A. Ravi "Performance analysis and comparison of Dirac video codec with H.264/MPEG4 part 10 AVC“, M.S. Thesis, EE Dept., University of Texas at Arlington, Aug. 2009.

27. [30] MSU video quality measurement tool : http://compression.ru/video/quality_measure/video_measurement_tool_en.htmlhttp://compression.ru/video/quality_measure/video_measurement_tool_en.html [31] S Xu and S. Wang, “Main program flow analysis in AVS-M”, 2nd International conference on networking and digital society (ICNDS), Vol. 2, pp. 621-624, May 2010. [32] F. Zhou and W. Xiong, “Realization and optimization of AVS coding algorithm ”, International Conference on system science, engineering design and manufacturing informatization (ICSEM), Vol. 1, pp. 282-285, Oct. 2011. [33] Dirac programmers’ guide: http://diracvideo.org/download/dirac-research/documentation/programmers_guide-1.0.0.pdfhttp://diracvideo.org/download/dirac-research/documentation/programmers_guide-1.0.0.pdf [34] Microsoft Visual C++ 2008 express edition: http://msdn.microsoft.com/en-us/express/future/bb421473 [35] Dirac algorithm: http://diracvideo.org/download/dirac-research/documentation/