iTextSharp.text.pdf.BarcodePDF417.CalculateErrorCorrection C# (CSharp) Метод

        protected void CalculateErrorCorrection(int dest) {
            if (errorLevel < 0 || errorLevel > 8)
                errorLevel = 0;
            int[] A = ERROR_LEVEL[errorLevel];
            int Alength = 2 << errorLevel;
            for (int k = 0; k < Alength; ++k)
                codewords[dest + k] = 0;
            int lastE = Alength - 1;
            for (int k = 0; k < lenCodewords; ++k) {
                int t1 = codewords[k] + codewords[dest];
                for (int e = 0; e <= lastE; ++e) {
                    int t2 = (t1 * A[lastE - e]) % MOD;
                    int t3 = MOD - t2;
                    codewords[dest + e] = ((e == lastE ? 0 : codewords[dest + e + 1]) + t3) % MOD;
                }
            }
            for (int k = 0; k < Alength; ++k)
                codewords[dest + k] = (MOD - codewords[dest + k]) % MOD;
        }