/// <summary>Initialize "qrCode" according to "numInputBytes", "ecLevel", and "mode".</summary> /// <remarks> /// Initialize "qrCode" according to "numInputBytes", "ecLevel", and "mode". On success, /// modify "qrCode". /// </remarks> /// <exception cref="iText.Barcodes.Qrcode.WriterException"/> private static void InitQRCode(int numInputBytes, ErrorCorrectionLevel ecLevel, int desiredMinVersion, Mode mode, QRCode qrCode) { qrCode.SetECLevel(ecLevel); qrCode.SetMode(mode); // In the following comments, we use numbers of Version 7-H. for (int versionNum = desiredMinVersion; versionNum <= 40; versionNum++) { Version version = Version.GetVersionForNumber(versionNum); // numBytes = 196 int numBytes = version.GetTotalCodewords(); // getNumECBytes = 130 Version.ECBlocks ecBlocks = version.GetECBlocksForLevel(ecLevel); int numEcBytes = ecBlocks.GetTotalECCodewords(); // getNumRSBlocks = 5 int numRSBlocks = ecBlocks.GetNumBlocks(); // 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.SetVersion(versionNum); qrCode.SetNumTotalBytes(numBytes); qrCode.SetNumDataBytes(numDataBytes); qrCode.SetNumRSBlocks(numRSBlocks); // getNumECBytes = 196 - 66 = 130 qrCode.SetNumECBytes(numEcBytes); // matrix width = 21 + 6 * 4 = 45 qrCode.SetMatrixWidth(version.GetDimensionForVersion()); return; } } throw new WriterException("Cannot find proper rs block info (input data too big?)"); }
// Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses // 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap). private static ByteMatrix RenderResult(QRCode code, int width, int height) { ByteMatrix input = code.GetMatrix(); int inputWidth = input.GetWidth(); int inputHeight = input.GetHeight(); int qrWidth = inputWidth + (QUIET_ZONE_SIZE << 1); int qrHeight = inputHeight + (QUIET_ZONE_SIZE << 1); int outputWidth = Math.Max(width, qrWidth); int outputHeight = Math.Max(height, qrHeight); int multiple = Math.Min(outputWidth / qrWidth, outputHeight / qrHeight); // Padding includes both the quiet zone and the extra white pixels to accommodate the requested // dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone. // If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will // handle all the padding from 100x100 (the actual QR) up to 200x160. int leftPadding = (outputWidth - (inputWidth * multiple)) / 2; int topPadding = (outputHeight - (inputHeight * multiple)) / 2; ByteMatrix output = new ByteMatrix(outputWidth, outputHeight); byte[][] outputArray = output.GetArray(); // We could be tricky and use the first row in each set of multiple as the temporary storage, // instead of allocating this separate array. byte[] row = new byte[outputWidth]; // 1. Write the white lines at the top for (int y = 0; y < topPadding; y++) { SetRowColor(outputArray[y], (byte)255); } // 2. Expand the QR image to the multiple byte[][] inputArray = input.GetArray(); for (int y = 0; y < inputHeight; y++) { // a. Write the white pixels at the left of each row for (int x = 0; x < leftPadding; x++) { row[x] = (byte)255; } // b. Write the contents of this row of the barcode int offset = leftPadding; for (int x = 0; x < inputWidth; x++) { byte value = (inputArray[y][x] == 1) ? (byte)0 : (byte)255; for (int z = 0; z < multiple; z++) { row[offset + z] = value; } offset += multiple; } // c. Write the white pixels at the right of each row offset = leftPadding + (inputWidth * multiple); for (int x = offset; x < outputWidth; x++) { row[x] = (byte)255; } // d. Write the completed row multiple times offset = topPadding + (y * multiple); for (int z = 0; z < multiple; z++) { Array.Copy(row, 0, outputArray[offset + z], 0, outputWidth); } } // 3. Write the white lines at the bottom int offset_1 = topPadding + (inputHeight * multiple); for (int y = offset_1; y < outputHeight; y++) { SetRowColor(outputArray[y], (byte)255); } return(output); }
/// <exception cref="iText.Barcodes.Qrcode.WriterException"/> public static void Encode(String content, ErrorCorrectionLevel ecLevel, IDictionary <EncodeHintType, Object > hints, QRCode qrCode) { String encoding = hints == null ? null : (String)hints.Get(EncodeHintType.CHARACTER_SET); if (encoding == null) { encoding = DEFAULT_BYTE_MODE_ENCODING; } // Step 1: Choose the mode (encoding). Mode mode = ChooseMode(content, encoding); // Step 2: Append "bytes" into "dataBits" in appropriate encoding. BitVector dataBits = new BitVector(); AppendBytes(content, mode, dataBits, encoding); // Step 3: Initialize QR code that can contain "dataBits". int numInputBytes = dataBits.SizeInBytes(); InitQRCode(numInputBytes, ecLevel, mode, qrCode); // Step 4: Build another bit vector that contains header and data. BitVector headerAndDataBits = new BitVector(); // Step 4.5: Append ECI message if applicable if (mode == Mode.BYTE && !DEFAULT_BYTE_MODE_ENCODING.Equals(encoding)) { CharacterSetECI eci = CharacterSetECI.GetCharacterSetECIByName(encoding); if (eci != null) { AppendECI(eci, headerAndDataBits); } } AppendModeInfo(mode, headerAndDataBits); int numLetters = mode.Equals(Mode.BYTE) ? dataBits.SizeInBytes() : content.Length; AppendLengthInfo(numLetters, qrCode.GetVersion(), mode, headerAndDataBits); headerAndDataBits.AppendBitVector(dataBits); // Step 5: Terminate the bits properly. TerminateBits(qrCode.GetNumDataBytes(), headerAndDataBits); // Step 6: Interleave data bits with error correction code. BitVector finalBits = new BitVector(); InterleaveWithECBytes(headerAndDataBits, qrCode.GetNumTotalBytes(), qrCode.GetNumDataBytes(), qrCode.GetNumRSBlocks (), finalBits); // Step 7: Choose the mask pattern and set to "qrCode". ByteMatrix matrix = new ByteMatrix(qrCode.GetMatrixWidth(), qrCode.GetMatrixWidth()); qrCode.SetMaskPattern(ChooseMaskPattern(finalBits, qrCode.GetECLevel(), qrCode.GetVersion(), matrix)); // Step 8. Build the matrix and set it to "qrCode". MatrixUtil.BuildMatrix(finalBits, qrCode.GetECLevel(), qrCode.GetVersion(), qrCode.GetMaskPattern(), matrix ); qrCode.SetMatrix(matrix); // Step 9. Make sure we have a valid QR Code. if (!qrCode.IsValid()) { throw new WriterException("Invalid QR code: " + qrCode.ToString()); } }
/// <summary>Encode "bytes" with the error correction level "ecLevel".</summary> /// <remarks> /// Encode "bytes" with the error correction level "ecLevel". The encoding mode will be chosen /// internally by chooseMode(). On success, store the result in "qrCode". /// We recommend you to use QRCode.EC_LEVEL_L (the lowest level) for /// "getECLevel" since our primary use is to show QR code on desktop screens. We don't need very /// strong error correction for this purpose. /// Note that there is no way to encode bytes in MODE_KANJI. We might want to add EncodeWithMode() /// with which clients can specify the encoding mode. For now, we don't need the functionality. /// </remarks> /// <exception cref="iText.Barcodes.Qrcode.WriterException"/> public static void Encode(String content, ErrorCorrectionLevel ecLevel, QRCode qrCode) { Encode(content, ecLevel, null, qrCode); }