Patent ID: 7200089

Claim:
A disk reproducing device comprising: a high-frequency emphasis filter to which a disk reproduction signal is input; a binarizing unit connected to said high-frequency emphasis filter and binarizing said disk reproduction signal; an error detecting unit connected to said binarizing unit and detecting an error in the binarized disk reproduction signal; a threshold adjusting unit connected to said error detecting unit and said binarizing unit and adjusting a threshold used for the binarization by said binarizing unit; a determining unit determining whether or not a disk to be reproduced is recorded with information in multisession; and a control unit correcting the threshold adjusted by said threshold adjusting unit based on the degree of asymmetry of said disk reproduction signal; wherein said binarizing unit, said error detecting unit, said threshold adjusting unit, and said control unit are configured to operate for each session of the disk to be reproduced when said determining unit determines that the disk to be reproduced is recorded with information in multisession.