non-uniform quantising logarithmic compression
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}).
(1995-02-21)