High density optical disc and method for reproducing and recording data thereof

A method, for reading data from a recording medium, comprising:

• (a) receiving a command to read data recorded in a given one of a lead-in area or a user-data area of the recording medium, wherein a length of a mark or space usable in the lead-in area to represent data is different than a length of a mark or space usable in the user-data area to represent data;
• and
• (b) selecting, based at least upon the length of a mark or space in the given area, one of differing at least first and second processing blocks to read the data recorded in the given area, the selected processing block not including a partial response and maximum likelihood (PRML) method if the given area is the lead-in area.

An apparatus for reading data from a recording medium, the apparatus comprising:

• (a) a signal processor including at least two processing blocks, at least one of the processing blocks being adapted to process data recorded in at least a lead-in area, and one or more different ones of the processing blocks being adapted to process data recorded in at least a user-data area, one of the at least two processing blocks including a block for a partial response and maximum likelihood (PRML) method;
• and
• (b) a controller to control the signal processor to select one of the at least two processing blocks and as such respectively process given data according to whether the given data is recorded in the lead-in area and the user-data area.