Abstract: A method of error correction comprises error correction coding processing and interleaving and de-interleaving processings for digital subcoding data (as opposed to main data) in subchannels (as opposed to the main channel) to be transmitted. Apparatus is provided comprising means for performing those processings. The method comprises the steps of dividing digital subcoding data in one PACKET into a plurality of PACKs; adding a first redundant code for error detection or error correction to each of the PACKs; and interleaving the digital subcoding data in each of the PACKs and the first redundant code; whereby the interleaved data is transmitted together with frame sync signals and main data. The data in the subchannels is coded and interleaved and then recorded so that the distances between the data are maximized.

Abstract: In apparatus for error correction in which data sequences containing blocks of data, previously arranged on a known time-base, and formed of data words and check words are written into a memory under control of a write address generator, and the data sequences are subsequently read out from the memory under control of a write address generator, so as to generate rearranged data sequences; during writing and reading of the data sequences, error correction is carried out by apparatus that includes an error correction arithmetic circuit for performing the error correction calculation, a pointer addition circuit for adding a pointer to the data words in association with an error state of the blocks, and a memory for memorizing a microprogram having fields to control the error correction arithmetic circuit and pointer addition circuit.

Abstract: An optical disc player comprises a rotating member for rotating the optical disc, an optical pickup member for reproducing a digital audio signal including an error correcting code such as the Reed-Solomon Code from the disc, an error correcting decoder for decoding the error correcting code so as to produce a corrected or interpolated digital audio signal and condition flag data indicating the correction of the digital audio signal, and a display for indicating the condition flag data as a stain or contamination condition of the disc.