ISO MPEG 1/2 及 Dolby AC-3 兩個標準廣泛應用於網路無線通訊多媒體系統及電影工業. 本論文將針對MPEG-1/2 and AC-3的模組提出設計.
音訊壓縮器如 MPEG-1/2 及 AC-3 均由濾波器組, 音響心理學模型,位元分配器, 立體聲矩陣及量化器等模組所構成. 本論文將針對以上模組提出設計方法. 首先, 簡介並歸納使用於ISO MPEG 1/2 及 Dolby AC-3 的各式濾波器組並提出一個單一的快速演算法. 在音響心理學模型部分, 提出以混合式濾波器組取代原來MPEG的頻率分析器以獲得快速計算. 在位元分配器及量化器部分,提出有效率的MPEG 及 AC-3位元分配器. 本論文同時對於立體聲的音響心理壓縮提出方法以達到更好的音訊壓縮品質

ISO MPEG 1/2 and Dolby AC-3 are widely used in the network, wireless, multimedia system and video industry. This dissertation studies the design of audio standards: MPEG-1/2 and AC-3.
The perceptual audio coder like MPEG-1/2 and AC-3 can be analyzed through filterbank, psychoacoustic model, stereo matrix, bit allocation/ quantization, and packing block. This dissertation considers the design for the filterbank, psychoacoustic model, stereo matrix, and bit allocation/ quantization. This dissertation summarizes the filterbanks adopted in coding standards and presents a unified fast algorithm for these filter banks. On the psychoacoustic models, the hybrid filterbank is proposed to replace to original frequency analyzer for MPEG audio standards to have efficient computing. On the bit allocation, we analyze the issues in bit allocation and present the efficient method. This dissertation also studies the stereo irrelevancy and presents the new method to achieve good quality.

List of Tablesvi
List of Figuresviii
Chapter 1 Introduction1
Chapter 2 Unified Algorithm for Fast Filterbank Computing6
2.1Introduction6
2.2Unified Form for the CMFBS10
2.2.1Unified form for the MCT in TDAC filterbank12
2.2.2Unified form for the variant of TDAC filterbanks20
2.2.3Unified form for the polyphase filterbank23
2.3Fast Algorithm for the Discrete Cosine Transform28
2.3.1Decomposition for type-II DCT28
2.3.2Decomposition for type-III DCT30
2.3.3Decomposition for type-IV DCT32
2.4Concluding Remarks35
Chapter 3 Fast Frequency Analysis for the Psychoacoustic Model38
3.1Introduction38
3.2Hybrid Filterbank for Psychoacoustic Model in MPEG39
3.2.1Filter response in hybrid filterbanks41
3.2.2Phase shifter & alias reduction44
3.2.3Complexity analysis48
3.2.4Cooperating with the intensity mode49
3.2.5Tonality measure50
3.2.6Effects of the hybrid filterbank and quality measurement52
3.3Concluding Remarks54
Chapter 4 Fast Bit Allocation Method55
4.1Introduction57
4.2Fast Bit Allocation Method in MPEG Layer 358
4.2.1Noise predictor for non-uniform quantizer60
4.2.2Fast bit allocation for non-uniform quantizer64
4.3Fast Bit Allocation Method in AC-369
4.3.1Addressed issues69
4.3.2Exponent coding method72
4.3.3Perceptual parameters74
4.3.4Experiment results79
4.3.5Remarks80
4.4Concluding Remarks82
Chapter 5 KL Transform for Intensity/Coupling Coding83
5.1Introduction83
5.2KL Transform for AC-384
5.2.1Addressed issues85
5.2.2Four proposed coupling methods87
5.2.3Experiments on the coupling methods93
5.2.4Dithering on the coupling bands95
5.2.5Remarks95
5.3KL Transform for MPEG Intensity Coding [35]97
5.4Concluding Remarks101
Chapter 6 Conclusions and Future Works102
6.1Concluding Remarks102
6.2Future Works102
Bibliography104
Curriculum Vita109
Publication Lists110

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