An Experimental High Fidelity Perceptual Audio Coder
Project in MUS420 Win 97

Bosse Lincoln
4561106
bosse@stanford.edu

• Contents
• Introduction
• Existing Coders and Standards
  • Subband Coders
    • MPEG-1, Layer I and II
  • Wavelet Coders
  • Transform Coders
    • MPEG-2 AAC
• Human Audio Perception: Masking
  • Basics
    • Absolute Threshold of Hearing
    • Implemented Model for ATH
    • Critical Bandwidths
  • Simultaneous Masking
    • Spreading Function
    • Implemented Model for Spreading Function
    • Tonality of Maskers
    • Implemented Model for Tonality
    • Implemented Model for Masking Threshold
    • Addition of Simultaneous Masking
  • Temporal Masking
    • Implemented Model for Post-Masking
    • Implemented Model for Pre-Masking
  • Quantization using the Masking Threshold
• Audio Coding
  • Transforming
    • Modified Discrete Cosine Transform (MDCT)
    • A Fast MDCT Implementation
    • Karhunen Lòeve Transform (KLT)
  • Quantization and Coding
    • Coefficient Clustering - Frequency Domain
    • Coefficient Clustering - Time Domain
    • Coefficient Quantization
    • Bit Coding
  • Stereo Coding
• Results and Conclusions
• References
• About this document ...