Patent attributes
In an optical disk of HD-DVD, data is recorded in both grooves and lands. A groove track includes its own data region called a groove (G) track address system formed therein and a land track includes its own data region called a land (L) track address system formed therein. When tracing a groove track, address information X is read from the G track address system, and also address information Y is read from the L track address system. If neither relationship X=Y or X=Y+1 is satisfied, it is determined that the address information X includes an error. Further, a groove track includes its own data region called a groove (G) track address system having a parity bit formed therein and a land track includes its own data region called a land (L) track address system having a parity bit formed therein. When tracing a groove track, address information X is read from the G track address system, and also address information Y is read from the L track address system. Even when the parity is correct, if neither relationship X=Y or X=Y+1 is satisfied, it is determined that the address information X includes an error.
