Exemple #1
0
        /// <summary> Append length info. On success, store the result in "bits".</summary>
        internal static void  appendLengthInfo(int numLetters, int version, Mode mode, BitVector bits)
        {
            int numBits = mode.getCharacterCountBits(Version.getVersionForNumber(version));

            if (numLetters > ((1 << numBits) - 1))
            {
                throw new WriterException(numLetters + "is bigger than" + ((1 << numBits) - 1));
            }
            bits.appendBits(numLetters, numBits);
        }
Exemple #2
0
        /// <summary> Initialize "qrCode" according to "numInputBytes", "ecLevel", and "mode". On success,
        /// modify "qrCode".
        /// </summary>
        private static void  InitQrCode(int numInputBytes, ErrorCorrectionLevel ecLevel, Mode mode, QRCode qrCode)
        {
            qrCode.ECLevel = ecLevel;
            qrCode.Mode    = mode;

            // In the following comments, we use numbers of Version 7-H.
            for (int versionNum = 1; versionNum <= 40; versionNum++)
            {
                Version version = Version.getVersionForNumber(versionNum);
                // numBytes = 196
                int numBytes = version.TotalCodewords;
                // getNumECBytes = 130
                Version.ECBlocks ecBlocks = version.getECBlocksForLevel(ecLevel);
                int numEcBytes            = ecBlocks.TotalECCodewords;
                // getNumRSBlocks = 5
                int numRSBlocks = ecBlocks.NumBlocks;
                // getNumDataBytes = 196 - 130 = 66
                int numDataBytes = numBytes - numEcBytes;
                // We want to choose the smallest version which can contain data of "numInputBytes" + some
                // extra bits for the header (mode info and length info). The header can be three bytes
                // (precisely 4 + 16 bits) at most. Hence we do +3 here.
                if (numDataBytes >= numInputBytes + 3)
                {
                    // Yay, we found the proper rs block info!
                    qrCode.Version       = versionNum;
                    qrCode.NumTotalBytes = numBytes;
                    qrCode.NumDataBytes  = numDataBytes;
                    qrCode.NumRSBlocks   = numRSBlocks;
                    // getNumECBytes = 196 - 66 = 130
                    qrCode.NumECBytes = numEcBytes;
                    // matrix width = 21 + 6 * 4 = 45
                    qrCode.MatrixWidth = version.DimensionForVersion;
                    return;
                }
            }
            throw new WriterException("Cannot find proper rs block info (input data too big?)");
        }