/// <summary> Initialize "QRCodeInternal" according to "numInputBytes", "m_EcLevelInternal", and "mode". On success, /// modify "QRCodeInternal". /// </summary> internal static void initQRCode(int numInputBytes, ErrorCorrectionLevelInternal m_EcLevelInternal, Mode mode, QRCodeInternal qrCodeInternal) { qrCodeInternal.EcLevelInternal = m_EcLevelInternal; qrCodeInternal.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(m_EcLevelInternal); 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! qrCodeInternal.Version = versionNum; qrCodeInternal.NumTotalBytes = numBytes; qrCodeInternal.NumDataBytes = numDataBytes; qrCodeInternal.NumRSBlocks = numRSBlocks; // getNumECBytes = 196 - 66 = 130 qrCodeInternal.NumECBytes = numEcBytes; // matrix width = 21 + 6 * 4 = 45 qrCodeInternal.MatrixWidth = version.DimensionForVersion; return; } } throw new WriterException("Cannot find proper rs block info (input data too big?)"); }
/// <summary> <p>When QR Codes use multiple data blocks, they are actually interleave the bytes of each of them. /// That is, the first byte of data block 1 to n is written, then the second bytes, and so on. This /// method will separate the data into original blocks.</p> /// /// </summary> /// <param name="rawCodewords">bytes as read directly from the QR Code /// </param> /// <param name="version">version of the QR Code /// </param> /// <param name="ecLevel">error-correction level of the QR Code /// </param> /// <returns> {@link DataBlock}s containing original bytes, "de-interleaved" from representation in the /// QR Code /// </returns> internal static DataBlock[] getDataBlocks(sbyte[] rawCodewords, Version version, ErrorCorrectionLevel ecLevel) { // Figure out the number and size of data blocks used by this version and // error correction level Version.ECBlocks ecBlocks = version.getECBlocksForLevel(ecLevel); // First count the total number of data blocks int totalBlocks = 0; Version.ECB[] ecBlockArray = ecBlocks.getECBlocks(); for (int i = 0; i < ecBlockArray.Length; i++) { totalBlocks += ecBlockArray[i].getCount(); } // Now establish DataBlocks of the appropriate size and number of data codewords DataBlock[] result = new DataBlock[totalBlocks]; int numResultBlocks = 0; for (int j = 0; j < ecBlockArray.Length; j++) { Version.ECB ecBlock = ecBlockArray[j]; for (int i = 0; i < ecBlock.getCount(); i++) { int numDataCodewords = ecBlock.getDataCodewords(); int numBlockCodewords = ecBlocks.getTotalECCodewords() + numDataCodewords; result[numResultBlocks++] = new DataBlock(numDataCodewords, new sbyte[numBlockCodewords]); } } // All blocks have the same amount of data, except that the last n // (where n may be 0) have 1 more byte. Figure out where these start. int shorterBlocksTotalCodewords = result[0].codewords.Length; int longerBlocksStartAt = result.Length - 1; while (longerBlocksStartAt >= 0) { int numCodewords = result[longerBlocksStartAt].codewords.Length; if (numCodewords == shorterBlocksTotalCodewords) { break; } if (numCodewords != shorterBlocksTotalCodewords + 1) { throw new System.SystemException("Data block sizes differ by more than 1"); } longerBlocksStartAt--; } longerBlocksStartAt++; int shorterBlocksNumDataCodewords = shorterBlocksTotalCodewords - ecBlocks.getTotalECCodewords(); // The last elements of result may be 1 element longer; // first fill out as many elements as all of them have int rawCodewordsOffset = 0; for (int i = 0; i < shorterBlocksNumDataCodewords; i++) { for (int j = 0; j < numResultBlocks; j++) { result[j].codewords[i] = rawCodewords[rawCodewordsOffset++]; } } // Fill out the last data block in the longer ones for (int j = longerBlocksStartAt; j < numResultBlocks; j++) { result[j].codewords[shorterBlocksNumDataCodewords] = rawCodewords[rawCodewordsOffset++]; } // Now add in error correction blocks int max = result[0].codewords.Length; for (int i = shorterBlocksNumDataCodewords; i < max; i++) { for (int j = 0; j < numResultBlocks; j++) { int iOffset = j < longerBlocksStartAt ? i : i + 1; result[j].codewords[iOffset] = rawCodewords[rawCodewordsOffset++]; } } if (rawCodewordsOffset != rawCodewords.Length) { throw new System.SystemException(); } return result; }
/// <summary> <p>When QR Codes use multiple data blocks, they are actually interleaved. /// That is, the first byte of data block 1 to n is written, then the second bytes, and so on. This /// method will separate the data into original blocks.</p> /// /// </summary> /// <param name="rawCodewords">bytes as read directly from the QR Code /// </param> /// <param name="version">version of the QR Code /// </param> /// <param name="ecLevel">error-correction level of the QR Code /// </param> /// <returns> {@link DataBlock}s containing original bytes, "de-interleaved" from representation in the /// QR Code /// </returns> internal static DataBlock[] getDataBlocks(sbyte[] rawCodewords, Version version, ErrorCorrectionLevel ecLevel) { if (rawCodewords.Length != version.TotalCodewords) { throw new System.ArgumentException(); } // Figure out the number and size of data blocks used by this version and // error correction level Version.ECBlocks ecBlocks = version.getECBlocksForLevel(ecLevel); // First count the total number of data blocks int totalBlocks = 0; Version.ECB[] ecBlockArray = ecBlocks.getECBlocks(); for (int i = 0; i < ecBlockArray.Length; i++) { totalBlocks += ecBlockArray[i].Count; } // Now establish DataBlocks of the appropriate size and number of data codewords DataBlock[] result = new DataBlock[totalBlocks]; int numResultBlocks = 0; for (int j = 0; j < ecBlockArray.Length; j++) { Version.ECB ecBlock = ecBlockArray[j]; for (int i = 0; i < ecBlock.Count; i++) { int numDataCodewords = ecBlock.DataCodewords; int numBlockCodewords = ecBlocks.ECCodewordsPerBlock + numDataCodewords; result[numResultBlocks++] = new DataBlock(numDataCodewords, new sbyte[numBlockCodewords]); } } // All blocks have the same amount of data, except that the last n // (where n may be 0) have 1 more byte. Figure out where these start. int shorterBlocksTotalCodewords = result[0].codewords.Length; int longerBlocksStartAt = result.Length - 1; while (longerBlocksStartAt >= 0) { int numCodewords = result[longerBlocksStartAt].codewords.Length; if (numCodewords == shorterBlocksTotalCodewords) { break; } longerBlocksStartAt--; } longerBlocksStartAt++; int shorterBlocksNumDataCodewords = shorterBlocksTotalCodewords - ecBlocks.ECCodewordsPerBlock; // The last elements of result may be 1 element longer; // first fill out as many elements as all of them have int rawCodewordsOffset = 0; for (int i = 0; i < shorterBlocksNumDataCodewords; i++) { for (int j = 0; j < numResultBlocks; j++) { result[j].codewords[i] = rawCodewords[rawCodewordsOffset++]; } } // Fill out the last data block in the longer ones for (int j = longerBlocksStartAt; j < numResultBlocks; j++) { result[j].codewords[shorterBlocksNumDataCodewords] = rawCodewords[rawCodewordsOffset++]; } // Now add in error correction blocks int max = result[0].codewords.Length; for (int i = shorterBlocksNumDataCodewords; i < max; i++) { for (int j = 0; j < numResultBlocks; j++) { int iOffset = j < longerBlocksStartAt?i:i + 1; result[j].codewords[iOffset] = rawCodewords[rawCodewordsOffset++]; } } return(result); }