Information reproducing device and information reproducing method

An information reproducing device, comprising:

• an analog-digital (AD) converter which samples an analog signal produced by reproducing information recorded on a magnetic recording medium, converts the analog signal to a digital signal, and outputs the digital signal together with position information of digital values corresponding to time elapse;
• a peak detecting unit which, upon receiving the digital value of the digital signal produced by the AD converter, detects a peak point corresponding to a position of an extreme value of a reproduced signal according to whether an inputted digital value exceeds a threshold, and the threshold is a judgment level set from the digital signal by following an output of the AD converter;
• and
• an information generating unit which generates a rectangular waveform signal of the reproduced signal, which is waveform-shaped according to an information of an interval between peaks detected at the peak detecting unit;
• wherein said peak detecting unit comprises:
• a judging section which, upon receiving the digital value of the digital signal produced by the AD converter, judges whether a current digital value has changed from a prior digital value;
• a holding section which holds the digital value of the digital signal produced by the AD converter as an extreme value and its position information;
• and
• an updating section which, when a judgment result of the judging section indicates that the current digital value has changed from the prior digital value, updates with the current digital value as an extreme value together with its position information, or when the current digital value matches the prior digital value, acquires an intermediate position between a position of the current digital value and a position of the prior digital value as a current extreme value position, holds a matching digital value as an extreme value and updates the position information with an intermediate position information.