Patent ID: 7617419

Claim:
An apparatus to manage random-directional scratches on a hard disk, comprising: a computer comprising a scratch determination unit which determines an m-th sector of an M-th track and an n-th sector of an N-th track to be affected by a single continuous scratch if the m-th sector of the M-th track and the n-th sector of the N-th track are defective, a difference between M and N is equal to a predetermined scratch treatment conditional value, and a difference between m and n is not larger than a predetermined scratch-treatment critical value; an in-between alleged defect setting unit which sets sectors between the m-th sector of the M-th track and the n-th sector of the N-th track as alleged defective sectors if the m-th sector of the M-th track and the n-th sector of the N-th track are determined to be affected by the single continuous scratch and the difference between m and n is larger than 1; and an either-end alleged defect setting unit which sets predetermined sectors around the m-th sector of the M-th track and the n-th sector of the N-th track as alleged defective sectors if the m-th sector of the M-th track and the n-th sector of the N-th track are determined to be affected by the single continuous scratch and the difference between m and n is smaller than the scratch-treatment critical value.