iTextSharp.text.pdf.qrcode.GF256Poly.MultiplyByMonomial C# (CSharp) Method

        internal GF256Poly MultiplyByMonomial(int degree, int coefficient) {
            if (degree < 0) {
                throw new ArgumentException();
            }
            if (coefficient == 0) {
                return field.GetZero();
            }
            int size = coefficients.Length;
            int[] product = new int[size + degree];
            for (int i = 0; i < size; i++) {
                product[i] = field.Multiply(coefficients[i], coefficient);
            }
            return new GF256Poly(field, product);
        }

        public void Encode(int[] toEncode, int ecBytes)
        {
            if (ecBytes == 0)
            {
                throw new ArgumentException("No error correction bytes");
            }
            var dataBytes = toEncode.Length - ecBytes;

            if (dataBytes <= 0)
            {
                throw new ArgumentException("No data bytes provided");
            }
            var generator        = BuildGenerator(ecBytes);
            var infoCoefficients = new int[dataBytes];

            System.Array.Copy(toEncode, 0, infoCoefficients, 0, dataBytes);
            var info = new GF256Poly(field, infoCoefficients);

            info = info.MultiplyByMonomial(ecBytes, 1);
            var remainder           = info.Divide(generator)[1];
            var coefficients        = remainder.GetCoefficients();
            var numZeroCoefficients = ecBytes - coefficients.Length;

            for (var i = 0; i < numZeroCoefficients; i++)
            {
                toEncode[dataBytes + i] = 0;
            }
            System.Array.Copy(coefficients, 0, toEncode, dataBytes + numZeroCoefficients, coefficients.Length);
        }