Implementation and comparison study of H.264 and AVS China EE 5359 Multimedia Processing Spring 2012 Guidance : Prof K R Rao Pavan Kumar Reddy Gajjala

Project Objective The project focuses on implementation and comparison of H.264 high profile with AVS China (part 2) video codec in terms of MSE (Mean Square Error), PSNR (Power to Signal Noise Ratio) and SSIM (Structural Similarity Index Metric), for various video test sequences. The motivation behind developing this project is, with introduction of several new standards for video compression there is a need to evaluate the performances and compare them among the available video coding standards.Currently the video coding standards that are evaluated are H.264 and AVS China.

Overview of H.264 H.264 or MPEG-4 part 10: AVC [4] is the next generation video codec developed by MPEG of ISO/IEC and VCEG of ITU-T, together known as the JVT (Joint Video Team). The H.264/MPEG-4 AVC standard, like previous standards, is based on motion compensated transform coding method. H.264 also uses hybrid block based video compression techniques such as transformation for reduction of spatial correlation, quantization for bit-rate control, motion compensated prediction for reduction of temporal correlation and entropy coding for reduction in statistical correlation Fig 1.1 shows the H.264 encoder block diagram and Fig 1.2 shows the H.264 decoder block diagram.

Fig. 1.1: H.264 encoder block diagram [4]

Fig. 1.2: H.264 decoder block diagram [4]

H.264/AVC profiles H.264 standard [1] is defined with a large variety of coding tools. This is done to make sure that standard caters to all classes of applications. However, not all tools are required for a particular application. So, the coding tools are segregated into different groups called profiles. The basic profiles defined in the standard are shown in Fig. 2

Fig. 2: Profile structure in H.264 [4]

AVS China AVS China is the compression standard of China which is also known as Audio video coding standard, developed with a target to develop same compression efficiency to H.264 but with lower computational complexity for SD(Standard Definition) and HD( High Definition)Videos. AVS Adopts the Classical block based prediction with transform coding framework. There are several parts developed with AVS China. [8] Table.1 describes the various parts of AVS China.

Fig 3: H.264 Encoder block diagram with unified loop Fig 3: H.264 Encoder block diagram with unified loop filter.[2] Table 1: Various parts of AVS China. [7]

The AVS China part 2 is one of the earliest and most important part of the AVS standard used in applications mainly used for HD broadcasting, high density storage media, video surveillances and video on demand. To acquire better tradeoff between coding efficiency and computational complexity advance coding tools intra and inter prediction tools, transform, quantization, entropy coding and de-blocking filter are adopted by AVS1-P2 (Part 2) [8]. The encoder and decoder architecture of AVS China are described in fig 3.1 and fig 3.2.

Fig. 3.1: AVS China Encoder Block Diagram [7]

Fig. 3.2 : AVS China Decoder Block Diagram [7]

Final results Simulation results for various test video sequences run using AVS China and H.264 are shown respectively along with the test bench conditions.(QP=31) Codec used: AVS China (RM09.12 reference software used-Jizhun profile) Test video sequence: Akiyo_qcif.yuv Format: 4:2:0 | Width: 176 | Height: 144 | Total Frames: 300 | Frames Encoded: 50 | Average MSE: | Average SSIM: |Average PSNR: | Encoding time: 93.38sec | Decoding time: 1.9sec |Bit rate 24 Hz: The Original and the encoded video sequence for Akiyo_qcif are shown in Fig 4.1

Fig 4.1:Original Video(left) and processed video(right) using AVS China Average MSE: | Average SSIM: |Average PSNR: |Compression ratio: 1.5:1

Codec used: H.264(JM 11.0 reference software used- High profile) Test video sequence: Akiyo_qcif.yuv Format: 4:2:0 | Width: 176 | Height: 144 | Total Frames: 300 | Frames Encoded: 50 | Average MSE: | Average SSIM: |Average PSNR: | Encoding time: sec | Decoding time: 3.056sec |Bit rate 30 Hz: The Original and the encoded video sequence for Akiyo_qcif are shown in Fig 4.2

Fig 4.2:Original Video(left) and processed video(right) using H.264(high profile) Average MSE: | Average SSIM: |Average PSNR: |Compression ratio: 3.03:1

Final Results comparison chart Various test sequences are used to compare the performances of H.264 and AVS China. TEST SEQMSEPSNRSSIMENCODE TIME(sec)DECODE TIME(sec)CODEC USED AKIYO AVS CHINA CARPHONE AVS CHINA COAST GUARD AVS CHINA CONTAINER AVS CHINA FOREMAN AVS CHINA AKIYO H.264 CARPHONE H.264 COAST GUARD H.264 CONTAINER H.264 FOREMAN H.264

Graphs showing the comparison of each parameter for different video sequences under AVS China and H.264 are shown in the following figures, fig 5.1 shows MSE, fig 5.2 shows PSNR, fig 5.3 shows SSIM, fig 5.4 shows encoding time, fig 5.5 shows decoding time respectively.

Fig 5.1: MSE comparison chart for AVS China and H.264

Fig 5.2: PSNR (in dB) comparison chart for AVS China and H.264

Fig 5.3: SSIM comparison chart for AVS China and H.264

Fig 5.4: Encoding time (in sec) comparison chart for AVS China and H.264

Fig 5.5: Decoding time (in sec) comparison chart for AVS China and H.264

Conclusions: Comparing the results for the test video sequences the encoding time and the decoding time of the AVS China are very less (nearly one third) when compared with H.264,although H.264 slightly outperforms AVS China in terms of MSE, PSNR and SSIM. However the overall objective qualities of all the encoded videos are similar.

ACRONYMS AND ABBREVIATIONS AVC: Advanced Video Coding CABAC: Context-based Adaptive Binary Arithmetic Coding CAVLC: Context-based Adaptive Variable Length Coding DLF: De-blocking Loop Filter DPB: Decoded Picture Buffer DVB: Digital Video Broadcasting FMO: Flexible Macro block Ordering GOP: Group of Pictures HD: High Definition ISO: International Standards Organization ITU: International Telecommunication Union JVT: Joint Video Team

LMSE: Least Mean Square Error MC: Motion Compensation MDCT: Modified Discrete Cosine Transform ME: Motion Estimation MPEG: Moving Picture Experts Group PIT: Pre-scaled Integer Transform PSNR: Peak Signal to Noise Ratio RDO: Rate Distortion Optimization SD: Standard Definition SI: Switching I SP: Switching P SSIM: Structural Similarity Index Metric VCEG: Video Coding Experts Group

References [1] Kwon Soon-kak, A Tamhankar and K R Rao, “Overview of H.264/MPEG-4 part 10”, 4 th EURASIP Conference on Video/Image Processing and Multimedia Communications, vol. 1, pp. 1-51, July [2] I. E. Richardson, “The H.264 advanced video compression standard”, 2 nd Edition, Wiley [3] H.264/AVC JM reference software. Website: [4]T. Wiegand, “Overview of the H.264/AVC video coding standard”, IEEE Trans. on Circuits and Systems for Video Technology, vol. 13, pp , Jul [5] Z. Wang et al, “Image quality assessment: from error visibility to structural similarity”, IEEE Trans. on Image processing, vol. 13, pp , April [6] X. Wang, “Recursive algorithms for linear LMSE estimators under uncertain observations”, IEEE Trans. on Automatic control, vol. 29, pp , Sep [7] L. Yu et al, “An Overview of AVS-Video: tools, performance and complexity”, Visual Communications and Image Processing 2005, Proc. of SPIE, vol. 5960, pp , July 31, [8] X. Wang et al, “Performance comparison of AVS and H.264/AVC video coding standards”, J Computer Science & Technology, vol.21, pp , May [9]AVS China part 2 video software, password protected: ftp:// /.ftp:// /

[10]B.Tang et al, “AVS encoder performance and complexity analysis based on mobile video communication”, WRI International conference on Communications and Mobile Computing, CMC ‘09, vol. 3, pp , Jan [11] S. Swaminathan and K.R. Rao, “Multiplexing and demultiplexing of AVS CHINA video with AAC audio,” International conference on TELSIKS, vol. 1, pp.84-91, 5-8 Oct [12] W. Gao et al, “AVS - The Chinese next-generation video coding standard” NAB, Las Vegas, [13] Z. Wang and A.C. Bovik, “A universal image quality index”, IEEE Signal Processing Letters, vol. 9, pp , March [14] Special issue on “AVS and its applications” Signal processing: Image Communication, vol. 24, pp , April [15]AVS Video Expert Group, “Information technology – Advanced coding of audio and video – Part 2: Video (AVS CHINA-P2 JQP FCD 1.0)”, Audio Video Coding Standard Group of China (AVS), Doc. AVS-N1538, Sep [16] F. Kamisli and J. S. Lim, “Video compression with 1-d directional transforms in H.264/AVC”, IEEE ICASSP, pp , Mar [17] D. Marpe, T. Wiegand and G. J. Sullivan, “The H.264/MPEG-4 AVC standard and its applications”, IEEE Communications Magazine, vol. 44, pp , Aug Website: [18] N. Jayant, “Frontiers of audiovisual communications: New convergences of broadband communications, computing, and rich media”, Proc. of the IEEE, vol. 100, April 2012.