The MPEG-1 Layer III (MP3) algorithm is one of the most successful audio formats for consumer audio storage and for transfer and playback of music on digital audio players. The MP3 compression standard along with the AAC (Advanced Audio Coding) algorithm are associated with the most successful music players of the last decade. This book describes the fundamentals and the MATLAB implementation details of the MP3 algorithm. Several of the tedious processes in MP3 are supported by demonstrations using MATLAB software. The book presents the theoretical concepts and algorithms used in the MP3 standard. The implementation details and simulations with MATLAB complement the theoretical principles. The extensive list of references enables the reader to perform a more detailed study on specific aspects of the algorithm and gain exposure to advancements in perceptual coding. Table of Contents: Introduction / Analysis Subband Filter Bank / Psychoacoustic Model II / MDCT / Bit Allocation, Quantization and Coding / Decoder
Author(s): Jayaraman J. Thiagarajan and Andreas Spanias
Series: Synthesis Lectures on Algorithms and Software in Engineering
Publisher: Morgan & Claypool
Year: 2012
Language: English
Pages: 129
Preface......Page 11
Acknowledgments......Page 13
A Brief History of Audio Coders......Page 15
Recent Audio Codecs......Page 16
A General Perceptual Audio Coding Architecture......Page 18
Principles of Psychoacoustics......Page 19
Psychoacoustic Model I......Page 22
Analysis Subband Filterbank......Page 23
Bit Allocation......Page 24
Summary......Page 25
Characteristics of the Analysis Filter Bank......Page 27
Filter Bank Implementation......Page 29
Framing......Page 32
Build Input Sample Vector......Page 33
Calculation of the Cosine Modulation Matrix......Page 34
Calculation of the Subband Samples......Page 35
Summary......Page 36
Analysis......Page 39
Computation of Energy and Unpredictability in Threshold Partitions......Page 42
Spreading Function and Excitation Pattern......Page 45
Tonality Index Estimation......Page 49
Calculation of Masking Thresholds for Threshold Partitions......Page 50
Pre-Echo Detection and Window Switching......Page 54
Estimation of SMR......Page 57
Summary......Page 59
MDCT Calculation......Page 61
Alias Reduction......Page 65
Summary......Page 67
Description......Page 71
Calculation of the Scalefactor Selection Information (scfsi)......Page 72
Distortion Control (Outer Loop)......Page 75
Non-Uniform Quantization......Page 79
Huffman Coding......Page 80
Bitstream Formatting......Page 87
Bit Reservoir......Page 88
Summary......Page 94
Synchronization and Error Checking......Page 95
Extracting Parameters for Huffman Decoding......Page 97
Extracting Parameters for Scalefactor Decoding......Page 98
Scalefactor Decoding......Page 100
Huffman Decoding......Page 102
Requantization......Page 104
Reordering......Page 105
The Inverse Modified Discrete Cosine Transform......Page 107
Polyphase Synthesis Filterbank......Page 108
Summary......Page 111
Complexity Profile of the MPEG-1 Layer III Algorithm......Page 115
Bibliography......Page 119
Authors' Biographies......Page 129
