A METHOD AND DEVICE FOR USE WITH HELICAL SCAN DATA RECORDING BY IMPLEMENTING A REED-SOLOMON PRODUCT CODE, A UNITARY MEDIUM COMPRISING SUCH DATA, AND A CASSETTE COMPRISING SUCH MEDIUM

摘要

Error protective data encoding for use with rotary head helical scan tape-recording is done by providing a first wordwise Reed-Solomon code along each recording track defined in first code words, and a second Reed-Solomon code defined in second code words. The first and second Reed-Solomon codes together form a product code format. Each second code word has a sequence of symbols across a plurality of contiguous tracks. The symbols of a single second code word have substantially uniform displacements between contiguous symbols both in a direction parallel to a length of the tape, and also in a direction perpendicular to a length of said tape. Each second code word extends substantially along a length of said tracks associated to the recording.