A permutation is a surface transformation which reorders groups of
eight-bit bytes. A 21 permutation exchanges pairs of successive
bytes. If the text contains an odd number of bytes, the last byte is
merely copied. An 4321 permutation inverts the order of quadruples
of bytes. If the text does not contains a multiple of four bytes, the
remaining bytes are nevertheless permuted as 321 if there are
three bytes, 21 if there are two bytes, or merely copied otherwise.
21
This surface is available in recode under the name
21-Permutation and has swabytes for an alias.
4321
This surface is available in recode under the name
4321-Permutation.
Please take a moment to fill out
this visitor survey You can help support this site by
visiting the advertisers that sponsor it! (only once each, though)
