In article , Jim H
wrote:
more from the 'Jim Lesurf school' of uk.rec.audio-ism:

Suposedly, you could also correct muliple bit errors, so long as there
is no more than one error on any row or column.

This is a potential problem if the 'parity bits' are only created in a
'2-dimensional array'. The reason is that if there are two bit errors in
the rectangle we can detect two row discrepencies and two column
discrepencies, but not know which of the rows is for which of the columns.
:-)

To solve this, more complex systems use 'multi-dimensional' arrangements.
These produce more 'parity bits' per block of data, and hence are less
efficient, but mean more than one error per block can be corrected.

The precise arrangements are often different in detail to what I describe,
but the real methods are all conceptually equivalent to the above.

Slainte,

Jim

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