On separating codes
نویسندگان
چکیده
Let Γ be a code of length n, and (T,U ) a pair of disjoint subsets of Γ. We say that (T,U ) is separated if there exists a coordinate i, such that for any codeword (c1, . . . , cn) ∈ T and any codeword (c ′ 1, . . . , c ′ n) ∈ U , ci 6= c ′ i. The code Γ is (t,u)-separating if all pairs (T,U ) with #T = t and #U = u are separated. Separating codes (or systems) are known from combinatorics, and they have also been applied, under various terminology, for watermarking. We present some new bounds, generalisations, and constructions for separating codes.
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