An ECC block is constituted by RS(248,216,33). Of a data length of 216
bytes (symbols), only 16 bytes are allocated to BCA data and the
remaining 200 bytes are used for fixed data having a predetermined value.
Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities
of 32 bytes (symbols) are caculated. Only the BCA data of 16 bytes and
the parities of the former 16 bytes of the 32-byte parities, that is, a
total of 32 bytes only, are recorded in a burst cutting area of an
optical disc. In decoding, error correction processing is carried out by
using the fixed data of 200 bytes. The unrecorded parities of 16 bytes
are processed as having been erased. Thus the error correction capability
in a burst cutting area of an optical disc can be improved.