The kind of compression often applied to a sound waveform. Logarithmic compression is a good match for the human ear's sensitivity but cannot handle zero amplitude (for which the logarithm is negative infinity). There are two standard compression functions which give a smooth transition between the logarithmic function and a linear segment passing through the origin: mu-law (North America) and A-law (ITU-T).
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Nearby terms: Non Return to Zero Inverted « nontrivial « Non-Uniform Memory Access « non-uniform quantising logarithmic compression » Non-Uniform Rational B Spline » non-volatile » non-volatile memory