Method and apparatus for error correction

Apparatus for processing digital data including main data and subcoding data ancillary thereto;

• comprising:
• means for grouping said subcoding data into a plurality of PACKETs, each PACKET comprising a plurality of PACKs, each PACK comprising a plurality of SYMBOLs and each SYMBOL comprising a plurality of bits;
• means for adding a first redundant code for error detection or error correction to each of said PACKs;
• and
• means for interleaving said subcoding data and said first redundant code in accordance with a first format to form interleaved data;
• and
• means for combining said interleaved data and said main data for transmission.

A method of error correction of data including n SYMBOLs representing a first kind of information and m SYMBOLs representing a second kind of information, each of said SYMBOLs comprising a plurality of bits;

• said method comprising the steps of:
• supplying said n SYMBOLs and encoding a first error detection code or error correction code to generate a redundant code of k SYMBOLs for said n SYMBOLs;
• supplying said m SYMBOLs and encoding a second error detection code or error correction code to generate a redundant code of l SYMBOLs for said m SYMBOLs;
• and
• interleaving said (n+k+m+l) SYMBOLs to form a series having a predetermined length of a plurality of SYMBOLs wherein the separations among said (n+k) SYMBOLs exceed those of said (m+l) SYMBOLs.

Apparatus for reproducing digital subcoding data ancillary to main data, the subcoding data being grouped into a plurality of PACKETs, each PACKET comprising a plurality of PACKs, each PACK comprising a plurality of SYMBOLs and each SYMBOL comprising a plurality of bits, said subcoding data and a first redundant code for error detection or error correction being interleaved in accordance with a first format to form interleaved data, said interleaved data being combined with said main data;

• said apparatus comprising:
• means responsive to said interleaved data and said main data for separating said interleaved data from said main data to form separated interleaved data;
• means responsive to said separated interleaved data for de-interleaving said subcoding data and said first redundant code in each of said PACKs to form de-interleaved data;
• and
• means for performing error detection or error correction on said de-interleaved data, thereby reproducing said subcoding data.