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Performance and Complexity Co-Evaluations of MPEG4-ALS Compression Standard for Low-Latency Music Compression

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Performance and Complexity Co-Evaluations of MPEG4-ALS Compression Standard for Low-Latency Music Compression Wright State University CORE Scholar Browse all Theses and Dissertations Theses and Dissertations 2008 Performance and Complexity Co-Evaluations of MPEG4-ALS Compression Standard for Low-Latency Music Compression Isaac Kevin Matthew Wright State University Follow this and additional works at: https://corescholar.libraries.wright.edu/etd_all Part of the Computer Sciences Commons Repository Citation Matthew, Isaac Kevin, "Performance and Complexity Co-Evaluations of MPEG4-ALS Compression Standard for Low-Latency Music Compression" (2008). Browse all Theses and Dissertations. 874. https://corescholar.libraries.wright.edu/etd_all/874 This Thesis is brought to you for free and open access by the Theses and Dissertations at CORE Scholar. It has been accepted for inclusion in Browse all Theses and Dissertations by an authorized administrator of CORE Scholar. For more information, please contact [email protected]. PERFORMANCE AND COMPLEXITY CO-EVALUATIONS OF MPEG4-ALS COMPRESSION STANDARD FOR LOW-LATENCY MUSIC COMPRESSION A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science (Computer Science ) By ISAAC KEVIN MATTHEW M. S. Physics 2 00 8 Wright State University WRIGHT STATE UNIVERSITY SCHOOL OF GRADUATE STUDIES 21 August, 2008 I HEREBY RECOMMEND THAT THE THESIS PREPARED UNDER MY SUPERVISION BY Isaac Kevin Matthew ENTITLED Performance and Complexity Co-evaluation of MPEG4-ALS Compression Standard for Low-latency Music Compression BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Master of Science, Computer Science. Dr. Yong Pei (Advisor) Assistant Professor, CS&E Thomas Sudkamp Interim Chair, CS&E Committee on Final Examination Dr. Yong Pei Assistant Professor, CS&E Dr. Bin Wang Associate Professor, CS&E Dr. Thomas Hartrum Assistant Research Professor, CS&E Joseph F. Thomas, Jr., Ph.D. Dean, School of Graduate Studies ABSTRACT Matthew, Isaac Kevin. M.S., Department of Computer Sciences & Engineering, Wright State University, 2008. Performance and Complexity Co-Evaluations of the MPEG4 ALS Compression Standard for Low-Latency Music Compression. In this thesis compression ratio and latency of different classical audio music tracks are analyzed with various encoder options of MPEG4–ALS. Different tracks of audio music tracks are tested with MPEG4-ALS coder with different options to find the optimum values for various parameters to obtain maximum compression ratio with minimum CPU time (encoder and decoder time). Optimum frame length for which the compression ratio saturates for music audio is found out by analyzing the results when different classical music tracks are experimented with various frame lengths. Also music tracks with varying sampling rate are tested and the compression ratio and latency relationship with sampling rate are analyzed and plotted. It is found that the compression gain rate was higher when the codec complexity is less, and joint channel correlation and long term correlations are not significant and latency trade off make the more complex codec options unsuitable for applications where latency is critical. When the two entropy coding options, Rice code and BGMC (Block Gilbert-Moore Codes) are applied on various classical music tracks, it was obvious that the Rice code is more suitable for low-latency applications compared to the more complex BGMC coding, as BGMC improved compression performance with the expense of latency, making it unsuitable in real-time applications. iii TABLE OF CONTENTS LIST OF FIGURES................................................................................................................ VII LIST OF TABLES .................................................................................................................... IX 1. INTRODUCTION ..............................................................................................................1 1.1 Objectives ............................................................................................................................................ 1 1.2 Data Compression .............................................................................................................................. 2 1.3 Speech Coding/Lossy Audio Coding ............................................................................................... 4 1.4 Lossless Audio Coding ....................................................................................................................... 5 1.4.1 The Basic Principle ...................................................................................................................... 6 1.4.2 Filter ............................................................................................................................................... 6 1.4.2.1 Prediction .................................................................................................................... 7 1.4.2.2 Stereo Decorrelation .................................................................................................. 8 1.4.3 Entropy Coding .......................................................................................................................... 9 1.5 Comparison of Lossless Codecs ................................................................................................... 10 1.6 Summary ............................................................................................................................................. 10 1.7 Organization of Thesis ..................................................................................................................... 11 2. INTERACTIVE MULTIMEDIA NETWORK APPLICATION ...................................................... 12 2.1 Telepresence ....................................................................................................................................... 12 2.2 Network Terminology ...................................................................................................................... 14 2.3 Network Delay (Latency) Factors ................................................................................................... 15 2.3.1 Propagation Delay .................................................................................................................... 15 2.3.2 Packetization Delay .................................................................................................................. 16 2.3.3 Processing Delay ...................................................................................................................... 16 2.3.4 Queuing Delay .......................................................................................................................... 17 2.3.5 Transmission Delay .................................................................................................................. 17 2.3.6 Coder Delay .............................................................................................................................. 18 2.3.7 De-Jitter Delay .......................................................................................................................... 18 2.4 Latency Requirment for Real Time Networking .......................................................................... 19 iv 2.5 Music Telepresence ........................................................................................................................... 21 2.5.1 Project Description .................................................................................................................. 22 2.5.2 Features Supported by the Project ........................................................................................ 23 2.5.3 Performance .............................................................................................................................. 24 2.6 Summary ............................................................................................................................................. 26 3. MPEG4-ALS ...................................................................................................................... 27 3.1 MPEG4-ALS Overview ................................................................................................................... 27 3.1.1 General Features ....................................................................................................................... 28 3.1.2 Codec Structure ......................................................................................................................... 29 3.1.2.1 Encoder Structure ........................................................................................................... 29 3.1.2.2 Decoder Structure ........................................................................................................... 31 3.1.3 Linear Predictive Coding .......................................................................................................... 32 3.1.4 Entropy Coding of Residual .................................................................................................... 35 3.1.5 Encoder Options ....................................................................................................................... 36 3.1.5.1 Block Length Switching ........................................................................................... 36 3.1.5.2 Random Access ........................................................................................................
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