Waveform equalizer for a reproduction signal obtained by reproducing marks and non-marks recorded on a recording medium

A waveform equalizer that equalizes a waveform of a reproduction signal obtained by reproducing marks and non-marks recorded on a recording medium, comprising:

• a delay element that delays a propagation of the reproduction signal;
• a plurality of multipliers that multiply predetermined coefficients by the reproduction signal and said delayed propagation reproduction signal;
• a detector that detects an asymmetry of the reproduction signal arising from physical profiles of each of the marks and the non-marks, said detector outputting a detection signal representing an amount of said asymmetry;
• a discriminator that outputs a discrimination signal in response to a discrimination of the marks and the non-marks;
• a calculator that calculates a first coefficient multiplied by the reproduction signal of the marks based on said outputted detection signal, said calculator calculating a second coefficient multiplied by the reproduction signal of the non-marks, which differs from the first coefficient;
• and
• a selector that selects one of said first coefficient and said second coefficient, based upon said outputted discriminating signal, wherein a number of said predetermined coefficients is odd, and wherein each of said first coefficient and said second coefficient selected by said selector is used as a center coefficient.