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The Concept
The Algorithm

    - Layer Coding Options
    - Hybrid Filter Bank
    - Psychoacoustics Model
    - Bit Allocation
The Psychoacoustic Model

The branch of psychoacoustics examines the concept of auditory masking and its effect on compression. Within each subband where blurring occurs the presence of a strong tonal signal can mask a region of weaker signals. This is evidenced in the following figure.

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If the noise resulting from approximation of sound data can be kept below the masking threshold for each partition, then the compression result should be indistinguishable from the original audio data.

Next step: Bit allocation

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