Add parts of zxing library to generate qr codes

6 files changed, 1672 insertions, 0 deletions

diff --git a/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/BlockPair.java b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/BlockPair.java
new file mode 100644
index 000000000..5714d9c3a
--- /dev/null
+++ b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/BlockPair.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+final class BlockPair {
+
+  private final byte[] dataBytes;
+  private final byte[] errorCorrectionBytes;
+
+  BlockPair(byte[] data, byte[] errorCorrection) {
+    dataBytes = data;
+    errorCorrectionBytes = errorCorrection;
+  }
+
+  public byte[] getDataBytes() {
+    return dataBytes;
+  }
+
+  public byte[] getErrorCorrectionBytes() {
+    return errorCorrectionBytes;
+  }
+
+}
diff --git a/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/ByteMatrix.java b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/ByteMatrix.java
new file mode 100644
index 000000000..eb248a26c
--- /dev/null
+++ b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/ByteMatrix.java
@@ -0,0 +1,97 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+/**
+ * A class which wraps a 2D array of bytes. The default usage is signed. If you want to use it as a
+ * unsigned container, it's up to you to do byteValue & 0xff at each location.
+ *
+ * JAVAPORT: The original code was a 2D array of ints, but since it only ever gets assigned
+ * -1, 0, and 1, I'm going to use less memory and go with bytes.
+ *
+ * @author dswitkin@google.com (Daniel Switkin)
+ */
+public final class ByteMatrix {
+
+  private final byte[][] bytes;
+  private final int width;
+  private final int height;
+
+  public ByteMatrix(int width, int height) {
+    bytes = new byte[height][width];
+    this.width = width;
+    this.height = height;
+  }
+
+  public int getHeight() {
+    return height;
+  }
+
+  public int getWidth() {
+    return width;
+  }
+
+  public byte get(int x, int y) {
+    return bytes[y][x];
+  }
+
+  public byte[][] getArray() {
+    return bytes;
+  }
+
+  public void set(int x, int y, byte value) {
+    bytes[y][x] = value;
+  }
+
+  public void set(int x, int y, int value) {
+    bytes[y][x] = (byte) value;
+  }
+
+  public void set(int x, int y, boolean value) {
+    bytes[y][x] = (byte) (value ? 1 : 0);
+  }
+
+  public void clear(byte value) {
+    for (int y = 0; y < height; ++y) {
+      for (int x = 0; x < width; ++x) {
+        bytes[y][x] = value;
+      }
+    }
+  }
+
+  public String toString() {
+    StringBuffer result = new StringBuffer(2 * width * height + 2);
+    for (int y = 0; y < height; ++y) {
+      for (int x = 0; x < width; ++x) {
+        switch (bytes[y][x]) {
+          case 0:
+            result.append(" 0");
+            break;
+          case 1:
+            result.append(" 1");
+            break;
+          default:
+            result.append("  ");
+            break;
+        }
+      }
+      result.append('\n');
+    }
+    return result.toString();
+  }
+
+}
diff --git a/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/Encoder.java b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/Encoder.java
new file mode 100644
index 000000000..8796511ab
--- /dev/null
+++ b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/Encoder.java
@@ -0,0 +1,557 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+import com.google.zxing.EncodeHintType;
+import com.google.zxing.WriterException;
+import com.google.zxing.common.BitArray;
+import com.google.zxing.common.CharacterSetECI;
+import com.google.zxing.common.ECI;
+import com.google.zxing.common.reedsolomon.GenericGF;
+import com.google.zxing.common.reedsolomon.ReedSolomonEncoder;
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+import com.google.zxing.qrcode.decoder.Mode;
+import com.google.zxing.qrcode.decoder.Version;
+
+import java.io.UnsupportedEncodingException;
+import java.util.Hashtable;
+import java.util.Vector;
+
+/**
+ * @author satorux@google.com (Satoru Takabayashi) - creator
+ * @author dswitkin@google.com (Daniel Switkin) - ported from C++
+ */
+public final class Encoder {
+
+  // The original table is defined in the table 5 of JISX0510:2004 (p.19).
+  private static final int[] ALPHANUMERIC_TABLE = {
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  // 0x00-0x0f
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  // 0x10-0x1f
+      36, -1, -1, -1, 37, 38, -1, -1, -1, -1, 39, 40, -1, 41, 42, 43,  // 0x20-0x2f
+      0,   1,  2,  3,  4,  5,  6,  7,  8,  9, 44, -1, -1, -1, -1, -1,  // 0x30-0x3f
+      -1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,  // 0x40-0x4f
+      25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, -1, -1, -1, -1, -1,  // 0x50-0x5f
+  };
+
+  static final String DEFAULT_BYTE_MODE_ENCODING = "ISO-8859-1";
+
+  private Encoder() {
+  }
+
+  // The mask penalty calculation is complicated.  See Table 21 of JISX0510:2004 (p.45) for details.
+  // Basically it applies four rules and summate all penalties.
+  private static int calculateMaskPenalty(ByteMatrix matrix) {
+    int penalty = 0;
+    penalty += MaskUtil.applyMaskPenaltyRule1(matrix);
+    penalty += MaskUtil.applyMaskPenaltyRule2(matrix);
+    penalty += MaskUtil.applyMaskPenaltyRule3(matrix);
+    penalty += MaskUtil.applyMaskPenaltyRule4(matrix);
+    return penalty;
+  }
+
+  /**
+   *  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.
+   */
+  public static void encode(String content, ErrorCorrectionLevel ecLevel, QRCode qrCode)
+      throws WriterException {
+    encode(content, ecLevel, null, qrCode);
+  }
+
+  public static void encode(String content, ErrorCorrectionLevel ecLevel, Hashtable hints,
+      QRCode qrCode) throws WriterException {
+
+    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.
+    BitArray dataBits = new BitArray();
+    appendBytes(content, mode, dataBits, encoding);
+    // Step 3: Initialize QR code that can contain "dataBits".
+    int numInputBytes = dataBits.getSizeInBytes();
+    initQRCode(numInputBytes, ecLevel, mode, qrCode);
+
+    // Step 4: Build another bit vector that contains header and data.
+    BitArray headerAndDataBits = new BitArray();
+
+    // 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.getSizeInBytes() : content.length();
+    appendLengthInfo(numLetters, qrCode.getVersion(), mode, headerAndDataBits);
+    headerAndDataBits.appendBitArray(dataBits);
+
+    // Step 5: Terminate the bits properly.
+    terminateBits(qrCode.getNumDataBytes(), headerAndDataBits);
+
+    // Step 6: Interleave data bits with error correction code.
+    BitArray finalBits = new BitArray();
+    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());
+    }
+  }
+
+  /**
+   * @return the code point of the table used in alphanumeric mode or
+   *  -1 if there is no corresponding code in the table.
+   */
+  static int getAlphanumericCode(int code) {
+    if (code < ALPHANUMERIC_TABLE.length) {
+      return ALPHANUMERIC_TABLE[code];
+    }
+    return -1;
+  }
+
+  public static Mode chooseMode(String content) {
+    return chooseMode(content, null);
+  }
+
+  /**
+   * Choose the best mode by examining the content. Note that 'encoding' is used as a hint;
+   * if it is Shift_JIS, and the input is only double-byte Kanji, then we return {@link Mode#KANJI}.
+   */
+  public static Mode chooseMode(String content, String encoding) {
+    if ("Shift_JIS".equals(encoding)) {
+      // Choose Kanji mode if all input are double-byte characters
+      return isOnlyDoubleByteKanji(content) ? Mode.KANJI : Mode.BYTE;
+    }
+    boolean hasNumeric = false;
+    boolean hasAlphanumeric = false;
+    for (int i = 0; i < content.length(); ++i) {
+      char c = content.charAt(i);
+      if (c >= '0' && c <= '9') {
+        hasNumeric = true;
+      } else if (getAlphanumericCode(c) != -1) {
+        hasAlphanumeric = true;
+      } else {
+        return Mode.BYTE;
+      }
+    }
+    if (hasAlphanumeric) {
+      return Mode.ALPHANUMERIC;
+    } else if (hasNumeric) {
+      return Mode.NUMERIC;
+    }
+    return Mode.BYTE;
+  }
+
+  private static boolean isOnlyDoubleByteKanji(String content) {
+    byte[] bytes;
+    try {
+      bytes = content.getBytes("Shift_JIS");
+    } catch (UnsupportedEncodingException uee) {
+      return false;
+    }
+    int length = bytes.length;
+    if (length % 2 != 0) {
+      return false;
+    }
+    for (int i = 0; i < length; i += 2) {
+      int byte1 = bytes[i] & 0xFF;
+      if ((byte1 < 0x81 || byte1 > 0x9F) && (byte1 < 0xE0 || byte1 > 0xEB)) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  private static int chooseMaskPattern(BitArray bits, ErrorCorrectionLevel ecLevel, int version,
+      ByteMatrix matrix) throws WriterException {
+
+    int minPenalty = Integer.MAX_VALUE;  // Lower penalty is better.
+    int bestMaskPattern = -1;
+    // We try all mask patterns to choose the best one.
+    for (int maskPattern = 0; maskPattern < QRCode.NUM_MASK_PATTERNS; maskPattern++) {
+      MatrixUtil.buildMatrix(bits, ecLevel, version, maskPattern, matrix);
+      int penalty = calculateMaskPenalty(matrix);
+      if (penalty < minPenalty) {
+        minPenalty = penalty;
+        bestMaskPattern = maskPattern;
+      }
+    }
+    return bestMaskPattern;
+  }
+
+  /**
+   * Initialize "qrCode" according to "numInputBytes", "ecLevel", and "mode". On success,
+   * modify "qrCode".
+   */
+  private static void initQRCode(int numInputBytes, ErrorCorrectionLevel ecLevel, Mode mode,
+      QRCode qrCode) throws WriterException {
+    qrCode.setECLevel(ecLevel);
+    qrCode.setMode(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.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?)");
+  }
+
+  /**
+   * Terminate bits as described in 8.4.8 and 8.4.9 of JISX0510:2004 (p.24).
+   */
+  static void terminateBits(int numDataBytes, BitArray bits) throws WriterException {
+    int capacity = numDataBytes << 3;
+    if (bits.getSize() > capacity) {
+      throw new WriterException("data bits cannot fit in the QR Code" + bits.getSize() + " > " +
+          capacity);
+    }
+    for (int i = 0; i < 4 && bits.getSize() < capacity; ++i) {
+      bits.appendBit(false);
+    }
+    // Append termination bits. See 8.4.8 of JISX0510:2004 (p.24) for details.
+    // If the last byte isn't 8-bit aligned, we'll add padding bits.
+    int numBitsInLastByte = bits.getSize() & 0x07;    
+    if (numBitsInLastByte > 0) {
+      for (int i = numBitsInLastByte; i < 8; i++) {
+        bits.appendBit(false);
+      }
+    }
+    // If we have more space, we'll fill the space with padding patterns defined in 8.4.9 (p.24).
+    int numPaddingBytes = numDataBytes - bits.getSizeInBytes();
+    for (int i = 0; i < numPaddingBytes; ++i) {
+      bits.appendBits((i & 0x01) == 0 ? 0xEC : 0x11, 8);
+    }
+    if (bits.getSize() != capacity) {
+      throw new WriterException("Bits size does not equal capacity");
+    }
+  }
+
+  /**
+   * Get number of data bytes and number of error correction bytes for block id "blockID". Store
+   * the result in "numDataBytesInBlock", and "numECBytesInBlock". See table 12 in 8.5.1 of
+   * JISX0510:2004 (p.30)
+   */
+  static void getNumDataBytesAndNumECBytesForBlockID(int numTotalBytes, int numDataBytes,
+      int numRSBlocks, int blockID, int[] numDataBytesInBlock,
+      int[] numECBytesInBlock) throws WriterException {
+    if (blockID >= numRSBlocks) {
+      throw new WriterException("Block ID too large");
+    }
+    // numRsBlocksInGroup2 = 196 % 5 = 1
+    int numRsBlocksInGroup2 = numTotalBytes % numRSBlocks;
+    // numRsBlocksInGroup1 = 5 - 1 = 4
+    int numRsBlocksInGroup1 = numRSBlocks - numRsBlocksInGroup2;
+    // numTotalBytesInGroup1 = 196 / 5 = 39
+    int numTotalBytesInGroup1 = numTotalBytes / numRSBlocks;
+    // numTotalBytesInGroup2 = 39 + 1 = 40
+    int numTotalBytesInGroup2 = numTotalBytesInGroup1 + 1;
+    // numDataBytesInGroup1 = 66 / 5 = 13
+    int numDataBytesInGroup1 = numDataBytes / numRSBlocks;
+    // numDataBytesInGroup2 = 13 + 1 = 14
+    int numDataBytesInGroup2 = numDataBytesInGroup1 + 1;
+    // numEcBytesInGroup1 = 39 - 13 = 26
+    int numEcBytesInGroup1 = numTotalBytesInGroup1 - numDataBytesInGroup1;
+    // numEcBytesInGroup2 = 40 - 14 = 26
+    int numEcBytesInGroup2 = numTotalBytesInGroup2 - numDataBytesInGroup2;
+    // Sanity checks.
+    // 26 = 26
+    if (numEcBytesInGroup1 != numEcBytesInGroup2) {
+      throw new WriterException("EC bytes mismatch");
+    }
+    // 5 = 4 + 1.
+    if (numRSBlocks != numRsBlocksInGroup1 + numRsBlocksInGroup2) {
+      throw new WriterException("RS blocks mismatch");
+    }
+    // 196 = (13 + 26) * 4 + (14 + 26) * 1
+    if (numTotalBytes !=
+        ((numDataBytesInGroup1 + numEcBytesInGroup1) *
+            numRsBlocksInGroup1) +
+            ((numDataBytesInGroup2 + numEcBytesInGroup2) *
+                numRsBlocksInGroup2)) {
+      throw new WriterException("Total bytes mismatch");
+    }
+
+    if (blockID < numRsBlocksInGroup1) {
+      numDataBytesInBlock[0] = numDataBytesInGroup1;
+      numECBytesInBlock[0] = numEcBytesInGroup1;
+    } else {
+      numDataBytesInBlock[0] = numDataBytesInGroup2;
+      numECBytesInBlock[0] = numEcBytesInGroup2;
+    }
+  }
+
+  /**
+   * Interleave "bits" with corresponding error correction bytes. On success, store the result in
+   * "result". The interleave rule is complicated. See 8.6 of JISX0510:2004 (p.37) for details.
+   */
+  static void interleaveWithECBytes(BitArray bits, int numTotalBytes,
+      int numDataBytes, int numRSBlocks, BitArray result) throws WriterException {
+
+    // "bits" must have "getNumDataBytes" bytes of data.
+    if (bits.getSizeInBytes() != numDataBytes) {
+      throw new WriterException("Number of bits and data bytes does not match");
+    }
+
+    // Step 1.  Divide data bytes into blocks and generate error correction bytes for them. We'll
+    // store the divided data bytes blocks and error correction bytes blocks into "blocks".
+    int dataBytesOffset = 0;
+    int maxNumDataBytes = 0;
+    int maxNumEcBytes = 0;
+
+    // Since, we know the number of reedsolmon blocks, we can initialize the vector with the number.
+    Vector blocks = new Vector(numRSBlocks);
+
+    for (int i = 0; i < numRSBlocks; ++i) {
+      int[] numDataBytesInBlock = new int[1];
+      int[] numEcBytesInBlock = new int[1];
+      getNumDataBytesAndNumECBytesForBlockID(
+          numTotalBytes, numDataBytes, numRSBlocks, i,
+          numDataBytesInBlock, numEcBytesInBlock);
+
+      int size = numDataBytesInBlock[0];
+      byte[] dataBytes = new byte[size];
+      bits.toBytes(8*dataBytesOffset, dataBytes, 0, size);
+      byte[] ecBytes = generateECBytes(dataBytes, numEcBytesInBlock[0]);
+      blocks.addElement(new BlockPair(dataBytes, ecBytes));
+
+      maxNumDataBytes = Math.max(maxNumDataBytes, size);
+      maxNumEcBytes = Math.max(maxNumEcBytes, ecBytes.length);
+      dataBytesOffset += numDataBytesInBlock[0];
+    }
+    if (numDataBytes != dataBytesOffset) {
+      throw new WriterException("Data bytes does not match offset");
+    }
+
+    // First, place data blocks.
+    for (int i = 0; i < maxNumDataBytes; ++i) {
+      for (int j = 0; j < blocks.size(); ++j) {
+        byte[] dataBytes = ((BlockPair) blocks.elementAt(j)).getDataBytes();
+        if (i < dataBytes.length) {
+          result.appendBits(dataBytes[i], 8);
+        }
+      }
+    }
+    // Then, place error correction blocks.
+    for (int i = 0; i < maxNumEcBytes; ++i) {
+      for (int j = 0; j < blocks.size(); ++j) {
+        byte[] ecBytes = ((BlockPair) blocks.elementAt(j)).getErrorCorrectionBytes();
+        if (i < ecBytes.length) {
+          result.appendBits(ecBytes[i], 8);
+        }
+      }
+    }
+    if (numTotalBytes != result.getSizeInBytes()) {  // Should be same.
+      throw new WriterException("Interleaving error: " + numTotalBytes + " and " +
+          result.getSizeInBytes() + " differ.");
+    }
+  }
+
+  static byte[] generateECBytes(byte[] dataBytes, int numEcBytesInBlock) {
+    int numDataBytes = dataBytes.length;
+    int[] toEncode = new int[numDataBytes + numEcBytesInBlock];
+    for (int i = 0; i < numDataBytes; i++) {
+      toEncode[i] = dataBytes[i] & 0xFF;
+    }
+    new ReedSolomonEncoder(GenericGF.QR_CODE_FIELD_256).encode(toEncode, numEcBytesInBlock);
+
+    byte[] ecBytes = new byte[numEcBytesInBlock];
+    for (int i = 0; i < numEcBytesInBlock; i++) {
+      ecBytes[i] = (byte) toEncode[numDataBytes + i];
+    }
+    return ecBytes;
+  }
+
+  /**
+   * Append mode info. On success, store the result in "bits".
+   */
+  static void appendModeInfo(Mode mode, BitArray bits) {
+    bits.appendBits(mode.getBits(), 4);
+  }
+
+
+  /**
+   * Append length info. On success, store the result in "bits".
+   */
+  static void appendLengthInfo(int numLetters, int version, Mode mode, BitArray bits)
+      throws WriterException {
+    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);
+  }
+
+  /**
+   * Append "bytes" in "mode" mode (encoding) into "bits". On success, store the result in "bits".
+   */
+  static void appendBytes(String content, Mode mode, BitArray bits, String encoding)
+      throws WriterException {
+    if (mode.equals(Mode.NUMERIC)) {
+      appendNumericBytes(content, bits);
+    } else if (mode.equals(Mode.ALPHANUMERIC)) {
+      appendAlphanumericBytes(content, bits);
+    } else if (mode.equals(Mode.BYTE)) {
+      append8BitBytes(content, bits, encoding);
+    } else if (mode.equals(Mode.KANJI)) {
+      appendKanjiBytes(content, bits);
+    } else {
+      throw new WriterException("Invalid mode: " + mode);
+    }
+  }
+
+  static void appendNumericBytes(String content, BitArray bits) {
+    int length = content.length();
+    int i = 0;
+    while (i < length) {
+      int num1 = content.charAt(i) - '0';
+      if (i + 2 < length) {
+        // Encode three numeric letters in ten bits.
+        int num2 = content.charAt(i + 1) - '0';
+        int num3 = content.charAt(i + 2) - '0';
+        bits.appendBits(num1 * 100 + num2 * 10 + num3, 10);
+        i += 3;
+      } else if (i + 1 < length) {
+        // Encode two numeric letters in seven bits.
+        int num2 = content.charAt(i + 1) - '0';
+        bits.appendBits(num1 * 10 + num2, 7);
+        i += 2;
+      } else {
+        // Encode one numeric letter in four bits.
+        bits.appendBits(num1, 4);
+        i++;
+      }
+    }
+  }
+
+  static void appendAlphanumericBytes(String content, BitArray bits) throws WriterException {
+    int length = content.length();
+    int i = 0;
+    while (i < length) {
+      int code1 = getAlphanumericCode(content.charAt(i));
+      if (code1 == -1) {
+        throw new WriterException();
+      }
+      if (i + 1 < length) {
+        int code2 = getAlphanumericCode(content.charAt(i + 1));
+        if (code2 == -1) {
+          throw new WriterException();
+        }
+        // Encode two alphanumeric letters in 11 bits.
+        bits.appendBits(code1 * 45 + code2, 11);
+        i += 2;
+      } else {
+        // Encode one alphanumeric letter in six bits.
+        bits.appendBits(code1, 6);
+        i++;
+      }
+    }
+  }
+
+  static void append8BitBytes(String content, BitArray bits, String encoding)
+      throws WriterException {
+    byte[] bytes;
+    try {
+      bytes = content.getBytes(encoding);
+    } catch (UnsupportedEncodingException uee) {
+      throw new WriterException(uee.toString());
+    }
+    for (int i = 0; i < bytes.length; ++i) {
+      bits.appendBits(bytes[i], 8);
+    }
+  }
+
+  static void appendKanjiBytes(String content, BitArray bits) throws WriterException {
+    byte[] bytes;
+    try {
+      bytes = content.getBytes("Shift_JIS");
+    } catch (UnsupportedEncodingException uee) {
+      throw new WriterException(uee.toString());
+    }
+    int length = bytes.length;
+    for (int i = 0; i < length; i += 2) {
+      int byte1 = bytes[i] & 0xFF;
+      int byte2 = bytes[i + 1] & 0xFF;
+      int code = (byte1 << 8) | byte2;
+      int subtracted = -1;
+      if (code >= 0x8140 && code <= 0x9ffc) {
+        subtracted = code - 0x8140;
+      } else if (code >= 0xe040 && code <= 0xebbf) {
+        subtracted = code - 0xc140;
+      }
+      if (subtracted == -1) {
+        throw new WriterException("Invalid byte sequence");
+      }
+      int encoded = ((subtracted >> 8) * 0xc0) + (subtracted & 0xff);
+      bits.appendBits(encoded, 13);
+    }
+  }
+
+  private static void appendECI(ECI eci, BitArray bits) {
+    bits.appendBits(Mode.ECI.getBits(), 4);
+    // This is correct for values up to 127, which is all we need now.
+    bits.appendBits(eci.getValue(), 8);
+  }
+
+}
diff --git a/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/MaskUtil.java b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/MaskUtil.java
new file mode 100644
index 000000000..61ccf48c1
--- /dev/null
+++ b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/MaskUtil.java
@@ -0,0 +1,218 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+/**
+ * @author satorux@google.com (Satoru Takabayashi) - creator
+ * @author dswitkin@google.com (Daniel Switkin) - ported from C++
+ */
+public final class MaskUtil {
+
+  private MaskUtil() {
+    // do nothing
+  }
+
+  // Apply mask penalty rule 1 and return the penalty. Find repetitive cells with the same color and
+  // give penalty to them. Example: 00000 or 11111.
+  public static int applyMaskPenaltyRule1(ByteMatrix matrix) {
+    return applyMaskPenaltyRule1Internal(matrix, true) + applyMaskPenaltyRule1Internal(matrix, false);
+  }
+
+  // Apply mask penalty rule 2 and return the penalty. Find 2x2 blocks with the same color and give
+  // penalty to them.
+  public static int applyMaskPenaltyRule2(ByteMatrix matrix) {
+    int penalty = 0;
+    byte[][] array = matrix.getArray();
+    int width = matrix.getWidth();
+    int height = matrix.getHeight();
+    for (int y = 0; y < height - 1; ++y) {
+      for (int x = 0; x < width - 1; ++x) {
+        int value = array[y][x];
+        if (value == array[y][x + 1] && value == array[y + 1][x] && value == array[y + 1][x + 1]) {
+          penalty += 3;
+        }
+      }
+    }
+    return penalty;
+  }
+
+  // Apply mask penalty rule 3 and return the penalty. Find consecutive cells of 00001011101 or
+  // 10111010000, and give penalty to them.  If we find patterns like 000010111010000, we give
+  // penalties twice (i.e. 40 * 2).
+  public static int applyMaskPenaltyRule3(ByteMatrix matrix) {
+    int penalty = 0;
+    byte[][] array = matrix.getArray();
+    int width = matrix.getWidth();
+    int height = matrix.getHeight();
+    for (int y = 0; y < height; ++y) {
+      for (int x = 0; x < width; ++x) {
+        // Tried to simplify following conditions but failed.
+        if (x + 6 < width &&
+            array[y][x] == 1 &&
+            array[y][x +  1] == 0 &&
+            array[y][x +  2] == 1 &&
+            array[y][x +  3] == 1 &&
+            array[y][x +  4] == 1 &&
+            array[y][x +  5] == 0 &&
+            array[y][x +  6] == 1 &&
+            ((x + 10 < width &&
+                array[y][x +  7] == 0 &&
+                array[y][x +  8] == 0 &&
+                array[y][x +  9] == 0 &&
+                array[y][x + 10] == 0) ||
+                (x - 4 >= 0 &&
+                    array[y][x -  1] == 0 &&
+                    array[y][x -  2] == 0 &&
+                    array[y][x -  3] == 0 &&
+                    array[y][x -  4] == 0))) {
+          penalty += 40;
+        }
+        if (y + 6 < height &&
+            array[y][x] == 1  &&
+            array[y +  1][x] == 0  &&
+            array[y +  2][x] == 1  &&
+            array[y +  3][x] == 1  &&
+            array[y +  4][x] == 1  &&
+            array[y +  5][x] == 0  &&
+            array[y +  6][x] == 1 &&
+            ((y + 10 < height &&
+                array[y +  7][x] == 0 &&
+                array[y +  8][x] == 0 &&
+                array[y +  9][x] == 0 &&
+                array[y + 10][x] == 0) ||
+                (y - 4 >= 0 &&
+                    array[y -  1][x] == 0 &&
+                    array[y -  2][x] == 0 &&
+                    array[y -  3][x] == 0 &&
+                    array[y -  4][x] == 0))) {
+          penalty += 40;
+        }
+      }
+    }
+    return penalty;
+  }
+
+  // Apply mask penalty rule 4 and return the penalty. Calculate the ratio of dark cells and give
+  // penalty if the ratio is far from 50%. It gives 10 penalty for 5% distance. Examples:
+  // -   0% => 100
+  // -  40% =>  20
+  // -  45% =>  10
+  // -  50% =>   0
+  // -  55% =>  10
+  // -  55% =>  20
+  // - 100% => 100
+  public static int applyMaskPenaltyRule4(ByteMatrix matrix) {
+    int numDarkCells = 0;
+    byte[][] array = matrix.getArray();
+    int width = matrix.getWidth();
+    int height = matrix.getHeight();
+    for (int y = 0; y < height; ++y) {
+      for (int x = 0; x < width; ++x) {
+        if (array[y][x] == 1) {
+          numDarkCells += 1;
+        }
+      }
+    }
+    int numTotalCells = matrix.getHeight() * matrix.getWidth();
+    double darkRatio = (double) numDarkCells / numTotalCells;
+    return Math.abs((int) (darkRatio * 100 - 50)) / 5 * 10;
+  }
+
+  // Return the mask bit for "getMaskPattern" at "x" and "y". See 8.8 of JISX0510:2004 for mask
+  // pattern conditions.
+  public static boolean getDataMaskBit(int maskPattern, int x, int y) {
+    if (!QRCode.isValidMaskPattern(maskPattern)) {
+      throw new IllegalArgumentException("Invalid mask pattern");
+    }
+    int intermediate;
+    int temp;
+    switch (maskPattern) {
+      case 0:
+        intermediate = (y + x) & 0x1;
+        break;
+      case 1:
+        intermediate = y & 0x1;
+        break;
+      case 2:
+        intermediate = x % 3;
+        break;
+      case 3:
+        intermediate = (y + x) % 3;
+        break;
+      case 4:
+        intermediate = ((y >>> 1) + (x / 3)) & 0x1;
+        break;
+      case 5:
+        temp = y * x;
+        intermediate = (temp & 0x1) + (temp % 3);
+        break;
+      case 6:
+        temp = y * x;
+        intermediate = ((temp & 0x1) + (temp % 3)) & 0x1;
+        break;
+      case 7:
+        temp = y * x;
+        intermediate = ((temp % 3) + ((y + x) & 0x1)) & 0x1;
+        break;
+      default:
+        throw new IllegalArgumentException("Invalid mask pattern: " + maskPattern);
+    }
+    return intermediate == 0;
+  }
+
+  // Helper function for applyMaskPenaltyRule1. We need this for doing this calculation in both
+  // vertical and horizontal orders respectively.
+  private static int applyMaskPenaltyRule1Internal(ByteMatrix matrix, boolean isHorizontal) {
+    int penalty = 0;
+    int numSameBitCells = 0;
+    int prevBit = -1;
+    // Horizontal mode:
+    //   for (int i = 0; i < matrix.height(); ++i) {
+    //     for (int j = 0; j < matrix.width(); ++j) {
+    //       int bit = matrix.get(i, j);
+    // Vertical mode:
+    //   for (int i = 0; i < matrix.width(); ++i) {
+    //     for (int j = 0; j < matrix.height(); ++j) {
+    //       int bit = matrix.get(j, i);
+    int iLimit = isHorizontal ? matrix.getHeight() : matrix.getWidth();
+    int jLimit = isHorizontal ? matrix.getWidth() : matrix.getHeight();
+    byte[][] array = matrix.getArray();
+    for (int i = 0; i < iLimit; ++i) {
+      for (int j = 0; j < jLimit; ++j) {
+        int bit = isHorizontal ? array[i][j] : array[j][i];
+        if (bit == prevBit) {
+          numSameBitCells += 1;
+          // Found five repetitive cells with the same color (bit).
+          // We'll give penalty of 3.
+          if (numSameBitCells == 5) {
+            penalty += 3;
+          } else if (numSameBitCells > 5) {
+            // After five repetitive cells, we'll add the penalty one
+            // by one.
+            penalty += 1;
+          }
+        } else {
+          numSameBitCells = 1;  // Include the cell itself.
+          prevBit = bit;
+        }
+      }
+      numSameBitCells = 0;  // Clear at each row/column.
+    }
+    return penalty;
+  }
+
+}
diff --git a/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/MatrixUtil.java b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/MatrixUtil.java
new file mode 100644
index 000000000..3d434e675
--- /dev/null
+++ b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/MatrixUtil.java
@@ -0,0 +1,524 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+import com.google.zxing.WriterException;
+import com.google.zxing.common.BitArray;
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+
+/**
+ * @author satorux@google.com (Satoru Takabayashi) - creator
+ * @author dswitkin@google.com (Daniel Switkin) - ported from C++
+ */
+public final class MatrixUtil {
+
+  private MatrixUtil() {
+    // do nothing
+  }
+
+  private static final int[][] POSITION_DETECTION_PATTERN =  {
+      {1, 1, 1, 1, 1, 1, 1},
+      {1, 0, 0, 0, 0, 0, 1},
+      {1, 0, 1, 1, 1, 0, 1},
+      {1, 0, 1, 1, 1, 0, 1},
+      {1, 0, 1, 1, 1, 0, 1},
+      {1, 0, 0, 0, 0, 0, 1},
+      {1, 1, 1, 1, 1, 1, 1},
+  };
+
+  private static final int[][] HORIZONTAL_SEPARATION_PATTERN = {
+      {0, 0, 0, 0, 0, 0, 0, 0},
+  };
+
+  private static final int[][] VERTICAL_SEPARATION_PATTERN = {
+      {0}, {0}, {0}, {0}, {0}, {0}, {0},
+  };
+
+  private static final int[][] POSITION_ADJUSTMENT_PATTERN = {
+      {1, 1, 1, 1, 1},
+      {1, 0, 0, 0, 1},
+      {1, 0, 1, 0, 1},
+      {1, 0, 0, 0, 1},
+      {1, 1, 1, 1, 1},
+  };
+
+  // From Appendix E. Table 1, JIS0510X:2004 (p 71). The table was double-checked by komatsu.
+  private static final int[][] POSITION_ADJUSTMENT_PATTERN_COORDINATE_TABLE = {
+      {-1, -1, -1, -1,  -1,  -1,  -1},  // Version 1
+      { 6, 18, -1, -1,  -1,  -1,  -1},  // Version 2
+      { 6, 22, -1, -1,  -1,  -1,  -1},  // Version 3
+      { 6, 26, -1, -1,  -1,  -1,  -1},  // Version 4
+      { 6, 30, -1, -1,  -1,  -1,  -1},  // Version 5
+      { 6, 34, -1, -1,  -1,  -1,  -1},  // Version 6
+      { 6, 22, 38, -1,  -1,  -1,  -1},  // Version 7
+      { 6, 24, 42, -1,  -1,  -1,  -1},  // Version 8
+      { 6, 26, 46, -1,  -1,  -1,  -1},  // Version 9
+      { 6, 28, 50, -1,  -1,  -1,  -1},  // Version 10
+      { 6, 30, 54, -1,  -1,  -1,  -1},  // Version 11
+      { 6, 32, 58, -1,  -1,  -1,  -1},  // Version 12
+      { 6, 34, 62, -1,  -1,  -1,  -1},  // Version 13
+      { 6, 26, 46, 66,  -1,  -1,  -1},  // Version 14
+      { 6, 26, 48, 70,  -1,  -1,  -1},  // Version 15
+      { 6, 26, 50, 74,  -1,  -1,  -1},  // Version 16
+      { 6, 30, 54, 78,  -1,  -1,  -1},  // Version 17
+      { 6, 30, 56, 82,  -1,  -1,  -1},  // Version 18
+      { 6, 30, 58, 86,  -1,  -1,  -1},  // Version 19
+      { 6, 34, 62, 90,  -1,  -1,  -1},  // Version 20
+      { 6, 28, 50, 72,  94,  -1,  -1},  // Version 21
+      { 6, 26, 50, 74,  98,  -1,  -1},  // Version 22
+      { 6, 30, 54, 78, 102,  -1,  -1},  // Version 23
+      { 6, 28, 54, 80, 106,  -1,  -1},  // Version 24
+      { 6, 32, 58, 84, 110,  -1,  -1},  // Version 25
+      { 6, 30, 58, 86, 114,  -1,  -1},  // Version 26
+      { 6, 34, 62, 90, 118,  -1,  -1},  // Version 27
+      { 6, 26, 50, 74,  98, 122,  -1},  // Version 28
+      { 6, 30, 54, 78, 102, 126,  -1},  // Version 29
+      { 6, 26, 52, 78, 104, 130,  -1},  // Version 30
+      { 6, 30, 56, 82, 108, 134,  -1},  // Version 31
+      { 6, 34, 60, 86, 112, 138,  -1},  // Version 32
+      { 6, 30, 58, 86, 114, 142,  -1},  // Version 33
+      { 6, 34, 62, 90, 118, 146,  -1},  // Version 34
+      { 6, 30, 54, 78, 102, 126, 150},  // Version 35
+      { 6, 24, 50, 76, 102, 128, 154},  // Version 36
+      { 6, 28, 54, 80, 106, 132, 158},  // Version 37
+      { 6, 32, 58, 84, 110, 136, 162},  // Version 38
+      { 6, 26, 54, 82, 110, 138, 166},  // Version 39
+      { 6, 30, 58, 86, 114, 142, 170},  // Version 40
+  };
+
+  // Type info cells at the left top corner.
+  private static final int[][] TYPE_INFO_COORDINATES = {
+      {8, 0},
+      {8, 1},
+      {8, 2},
+      {8, 3},
+      {8, 4},
+      {8, 5},
+      {8, 7},
+      {8, 8},
+      {7, 8},
+      {5, 8},
+      {4, 8},
+      {3, 8},
+      {2, 8},
+      {1, 8},
+      {0, 8},
+  };
+
+  // From Appendix D in JISX0510:2004 (p. 67)
+  private static final int VERSION_INFO_POLY = 0x1f25;  // 1 1111 0010 0101
+
+  // From Appendix C in JISX0510:2004 (p.65).
+  private static final int TYPE_INFO_POLY = 0x537;
+  private static final int TYPE_INFO_MASK_PATTERN = 0x5412;
+
+  // Set all cells to -1.  -1 means that the cell is empty (not set yet).
+  //
+  // JAVAPORT: We shouldn't need to do this at all. The code should be rewritten to begin encoding
+  // with the ByteMatrix initialized all to zero.
+  public static void clearMatrix(ByteMatrix matrix) {
+    matrix.clear((byte) -1);
+  }
+
+  // Build 2D matrix of QR Code from "dataBits" with "ecLevel", "version" and "getMaskPattern". On
+  // success, store the result in "matrix" and return true.
+  public static void buildMatrix(BitArray dataBits, ErrorCorrectionLevel ecLevel, int version,
+      int maskPattern, ByteMatrix matrix) throws WriterException {
+    clearMatrix(matrix);
+    embedBasicPatterns(version, matrix);
+    // Type information appear with any version.
+    embedTypeInfo(ecLevel, maskPattern, matrix);
+    // Version info appear if version >= 7.
+    maybeEmbedVersionInfo(version, matrix);
+    // Data should be embedded at end.
+    embedDataBits(dataBits, maskPattern, matrix);
+  }
+
+  // Embed basic patterns. On success, modify the matrix and return true.
+  // The basic patterns are:
+  // - Position detection patterns
+  // - Timing patterns
+  // - Dark dot at the left bottom corner
+  // - Position adjustment patterns, if need be
+  public static void embedBasicPatterns(int version, ByteMatrix matrix) throws WriterException {
+    // Let's get started with embedding big squares at corners.
+    embedPositionDetectionPatternsAndSeparators(matrix);
+    // Then, embed the dark dot at the left bottom corner.
+    embedDarkDotAtLeftBottomCorner(matrix);
+
+    // Position adjustment patterns appear if version >= 2.
+    maybeEmbedPositionAdjustmentPatterns(version, matrix);
+    // Timing patterns should be embedded after position adj. patterns.
+    embedTimingPatterns(matrix);
+  }
+
+  // Embed type information. On success, modify the matrix.
+  public static void embedTypeInfo(ErrorCorrectionLevel ecLevel, int maskPattern, ByteMatrix matrix)
+      throws WriterException {
+    BitArray typeInfoBits = new BitArray();
+    makeTypeInfoBits(ecLevel, maskPattern, typeInfoBits);
+
+    for (int i = 0; i < typeInfoBits.getSize(); ++i) {
+      // Place bits in LSB to MSB order.  LSB (least significant bit) is the last value in
+      // "typeInfoBits".
+      boolean bit = typeInfoBits.get(typeInfoBits.getSize() - 1 - i);
+
+      // Type info bits at the left top corner. See 8.9 of JISX0510:2004 (p.46).
+      int x1 = TYPE_INFO_COORDINATES[i][0];
+      int y1 = TYPE_INFO_COORDINATES[i][1];
+      matrix.set(x1, y1, bit);
+
+      if (i < 8) {
+        // Right top corner.
+        int x2 = matrix.getWidth() - i - 1;
+        int y2 = 8;
+        matrix.set(x2, y2, bit);
+      } else {
+        // Left bottom corner.
+        int x2 = 8;
+        int y2 = matrix.getHeight() - 7 + (i - 8);
+        matrix.set(x2, y2, bit);
+      }
+    }
+  }
+
+  // Embed version information if need be. On success, modify the matrix and return true.
+  // See 8.10 of JISX0510:2004 (p.47) for how to embed version information.
+  public static void maybeEmbedVersionInfo(int version, ByteMatrix matrix) throws WriterException {
+    if (version < 7) {  // Version info is necessary if version >= 7.
+      return;  // Don't need version info.
+    }
+    BitArray versionInfoBits = new BitArray();
+    makeVersionInfoBits(version, versionInfoBits);
+
+    int bitIndex = 6 * 3 - 1;  // It will decrease from 17 to 0.
+    for (int i = 0; i < 6; ++i) {
+      for (int j = 0; j < 3; ++j) {
+        // Place bits in LSB (least significant bit) to MSB order.
+        boolean bit = versionInfoBits.get(bitIndex);
+        bitIndex--;
+        // Left bottom corner.
+        matrix.set(i, matrix.getHeight() - 11 + j, bit);
+        // Right bottom corner.
+        matrix.set(matrix.getHeight() - 11 + j, i, bit);
+      }
+    }
+  }
+
+  // Embed "dataBits" using "getMaskPattern". On success, modify the matrix and return true.
+  // For debugging purposes, it skips masking process if "getMaskPattern" is -1.
+  // See 8.7 of JISX0510:2004 (p.38) for how to embed data bits.
+  public static void embedDataBits(BitArray dataBits, int maskPattern, ByteMatrix matrix)
+      throws WriterException {
+    int bitIndex = 0;
+    int direction = -1;
+    // Start from the right bottom cell.
+    int x = matrix.getWidth() - 1;
+    int y = matrix.getHeight() - 1;
+    while (x > 0) {
+      // Skip the vertical timing pattern.
+      if (x == 6) {
+        x -= 1;
+      }
+      while (y >= 0 && y < matrix.getHeight()) {
+        for (int i = 0; i < 2; ++i) {
+          int xx = x - i;
+          // Skip the cell if it's not empty.
+          if (!isEmpty(matrix.get(xx, y))) {
+            continue;
+          }
+          boolean bit;
+          if (bitIndex < dataBits.getSize()) {
+            bit = dataBits.get(bitIndex);
+            ++bitIndex;
+          } else {
+            // Padding bit. If there is no bit left, we'll fill the left cells with 0, as described
+            // in 8.4.9 of JISX0510:2004 (p. 24).
+            bit = false;
+          }
+
+          // Skip masking if mask_pattern is -1.
+          if (maskPattern != -1) {
+            if (MaskUtil.getDataMaskBit(maskPattern, xx, y)) {
+              bit = !bit;
+            }
+          }
+          matrix.set(xx, y, bit);
+        }
+        y += direction;
+      }
+      direction = -direction;  // Reverse the direction.
+      y += direction;
+      x -= 2;  // Move to the left.
+    }
+    // All bits should be consumed.
+    if (bitIndex != dataBits.getSize()) {
+      throw new WriterException("Not all bits consumed: " + bitIndex + '/' + dataBits.getSize());
+    }
+  }
+
+  // Return the position of the most significant bit set (to one) in the "value". The most
+  // significant bit is position 32. If there is no bit set, return 0. Examples:
+  // - findMSBSet(0) => 0
+  // - findMSBSet(1) => 1
+  // - findMSBSet(255) => 8
+  public static int findMSBSet(int value) {
+    int numDigits = 0;
+    while (value != 0) {
+      value >>>= 1;
+      ++numDigits;
+    }
+    return numDigits;
+  }
+
+  // Calculate BCH (Bose-Chaudhuri-Hocquenghem) code for "value" using polynomial "poly". The BCH
+  // code is used for encoding type information and version information.
+  // Example: Calculation of version information of 7.
+  // f(x) is created from 7.
+  //   - 7 = 000111 in 6 bits
+  //   - f(x) = x^2 + x^1 + x^0
+  // g(x) is given by the standard (p. 67)
+  //   - g(x) = x^12 + x^11 + x^10 + x^9 + x^8 + x^5 + x^2 + 1
+  // Multiply f(x) by x^(18 - 6)
+  //   - f'(x) = f(x) * x^(18 - 6)
+  //   - f'(x) = x^14 + x^13 + x^12
+  // Calculate the remainder of f'(x) / g(x)
+  //         x^2
+  //         __________________________________________________
+  //   g(x) )x^14 + x^13 + x^12
+  //         x^14 + x^13 + x^12 + x^11 + x^10 + x^7 + x^4 + x^2
+  //         --------------------------------------------------
+  //                              x^11 + x^10 + x^7 + x^4 + x^2
+  //
+  // The remainder is x^11 + x^10 + x^7 + x^4 + x^2
+  // Encode it in binary: 110010010100
+  // The return value is 0xc94 (1100 1001 0100)
+  //
+  // Since all coefficients in the polynomials are 1 or 0, we can do the calculation by bit
+  // operations. We don't care if cofficients are positive or negative.
+  public static int calculateBCHCode(int value, int poly) {
+    // If poly is "1 1111 0010 0101" (version info poly), msbSetInPoly is 13. We'll subtract 1
+    // from 13 to make it 12.
+    int msbSetInPoly = findMSBSet(poly);
+    value <<= msbSetInPoly - 1;
+    // Do the division business using exclusive-or operations.
+    while (findMSBSet(value) >= msbSetInPoly) {
+      value ^= poly << (findMSBSet(value) - msbSetInPoly);
+    }
+    // Now the "value" is the remainder (i.e. the BCH code)
+    return value;
+  }
+
+  // Make bit vector of type information. On success, store the result in "bits" and return true.
+  // Encode error correction level and mask pattern. See 8.9 of
+  // JISX0510:2004 (p.45) for details.
+  public static void makeTypeInfoBits(ErrorCorrectionLevel ecLevel, int maskPattern, BitArray bits)
+      throws WriterException {
+    if (!QRCode.isValidMaskPattern(maskPattern)) {
+      throw new WriterException("Invalid mask pattern");
+    }
+    int typeInfo = (ecLevel.getBits() << 3) | maskPattern;
+    bits.appendBits(typeInfo, 5);
+
+    int bchCode = calculateBCHCode(typeInfo, TYPE_INFO_POLY);
+    bits.appendBits(bchCode, 10);
+
+    BitArray maskBits = new BitArray();
+    maskBits.appendBits(TYPE_INFO_MASK_PATTERN, 15);
+    bits.xor(maskBits);
+
+    if (bits.getSize() != 15) {  // Just in case.
+      throw new WriterException("should not happen but we got: " + bits.getSize());
+    }
+  }
+
+  // Make bit vector of version information. On success, store the result in "bits" and return true.
+  // See 8.10 of JISX0510:2004 (p.45) for details.
+  public static void makeVersionInfoBits(int version, BitArray bits) throws WriterException {
+    bits.appendBits(version, 6);
+    int bchCode = calculateBCHCode(version, VERSION_INFO_POLY);
+    bits.appendBits(bchCode, 12);
+
+    if (bits.getSize() != 18) {  // Just in case.
+      throw new WriterException("should not happen but we got: " + bits.getSize());
+    }
+  }
+
+  // Check if "value" is empty.
+  private static boolean isEmpty(int value) {
+    return value == -1;
+  }
+
+  // Check if "value" is valid.
+  private static boolean isValidValue(int value) {
+    return value == -1 ||  // Empty.
+        value == 0 ||  // Light (white).
+        value == 1;  // Dark (black).
+  }
+
+  private static void embedTimingPatterns(ByteMatrix matrix) throws WriterException {
+    // -8 is for skipping position detection patterns (size 7), and two horizontal/vertical
+    // separation patterns (size 1). Thus, 8 = 7 + 1.
+    for (int i = 8; i < matrix.getWidth() - 8; ++i) {
+      int bit = (i + 1) % 2;
+      // Horizontal line.
+      if (!isValidValue(matrix.get(i, 6))) {
+        throw new WriterException();
+      }
+      if (isEmpty(matrix.get(i, 6))) {
+        matrix.set(i, 6, bit);
+      }
+      // Vertical line.
+      if (!isValidValue(matrix.get(6, i))) {
+        throw new WriterException();
+      }
+      if (isEmpty(matrix.get(6, i))) {
+        matrix.set(6, i, bit);
+      }
+    }
+  }
+
+  // Embed the lonely dark dot at left bottom corner. JISX0510:2004 (p.46)
+  private static void embedDarkDotAtLeftBottomCorner(ByteMatrix matrix) throws WriterException {
+    if (matrix.get(8, matrix.getHeight() - 8) == 0) {
+      throw new WriterException();
+    }
+    matrix.set(8, matrix.getHeight() - 8, 1);
+  }
+
+  private static void embedHorizontalSeparationPattern(int xStart, int yStart,
+      ByteMatrix matrix) throws WriterException {
+    // We know the width and height.
+    if (HORIZONTAL_SEPARATION_PATTERN[0].length != 8 || HORIZONTAL_SEPARATION_PATTERN.length != 1) {
+      throw new WriterException("Bad horizontal separation pattern");
+    }
+    for (int x = 0; x < 8; ++x) {
+      if (!isEmpty(matrix.get(xStart + x, yStart))) {
+        throw new WriterException();
+      }
+      matrix.set(xStart + x, yStart, HORIZONTAL_SEPARATION_PATTERN[0][x]);
+    }
+  }
+
+  private static void embedVerticalSeparationPattern(int xStart, int yStart,
+      ByteMatrix matrix) throws WriterException {
+    // We know the width and height.
+    if (VERTICAL_SEPARATION_PATTERN[0].length != 1 || VERTICAL_SEPARATION_PATTERN.length != 7) {
+      throw new WriterException("Bad vertical separation pattern");
+    }
+    for (int y = 0; y < 7; ++y) {
+      if (!isEmpty(matrix.get(xStart, yStart + y))) {
+        throw new WriterException();
+      }
+      matrix.set(xStart, yStart + y, VERTICAL_SEPARATION_PATTERN[y][0]);
+    }
+  }
+
+  // Note that we cannot unify the function with embedPositionDetectionPattern() despite they are
+  // almost identical, since we cannot write a function that takes 2D arrays in different sizes in
+  // C/C++. We should live with the fact.
+  private static void embedPositionAdjustmentPattern(int xStart, int yStart,
+      ByteMatrix matrix) throws WriterException {
+    // We know the width and height.
+    if (POSITION_ADJUSTMENT_PATTERN[0].length != 5 || POSITION_ADJUSTMENT_PATTERN.length != 5) {
+      throw new WriterException("Bad position adjustment");
+    }
+    for (int y = 0; y < 5; ++y) {
+      for (int x = 0; x < 5; ++x) {
+        if (!isEmpty(matrix.get(xStart + x, yStart + y))) {
+          throw new WriterException();
+        }
+        matrix.set(xStart + x, yStart + y, POSITION_ADJUSTMENT_PATTERN[y][x]);
+      }
+    }
+  }
+
+  private static void embedPositionDetectionPattern(int xStart, int yStart,
+      ByteMatrix matrix) throws WriterException {
+    // We know the width and height.
+    if (POSITION_DETECTION_PATTERN[0].length != 7 || POSITION_DETECTION_PATTERN.length != 7) {
+      throw new WriterException("Bad position detection pattern");
+    }
+    for (int y = 0; y < 7; ++y) {
+      for (int x = 0; x < 7; ++x) {
+        if (!isEmpty(matrix.get(xStart + x, yStart + y))) {
+          throw new WriterException();
+        }
+        matrix.set(xStart + x, yStart + y, POSITION_DETECTION_PATTERN[y][x]);
+      }
+    }
+  }
+
+  // Embed position detection patterns and surrounding vertical/horizontal separators.
+  private static void embedPositionDetectionPatternsAndSeparators(ByteMatrix matrix) throws WriterException {
+    // Embed three big squares at corners.
+    int pdpWidth = POSITION_DETECTION_PATTERN[0].length;
+    // Left top corner.
+    embedPositionDetectionPattern(0, 0, matrix);
+    // Right top corner.
+    embedPositionDetectionPattern(matrix.getWidth() - pdpWidth, 0, matrix);
+    // Left bottom corner.
+    embedPositionDetectionPattern(0, matrix.getWidth() - pdpWidth, matrix);
+
+    // Embed horizontal separation patterns around the squares.
+    int hspWidth = HORIZONTAL_SEPARATION_PATTERN[0].length;
+    // Left top corner.
+    embedHorizontalSeparationPattern(0, hspWidth - 1, matrix);
+    // Right top corner.
+    embedHorizontalSeparationPattern(matrix.getWidth() - hspWidth,
+        hspWidth - 1, matrix);
+    // Left bottom corner.
+    embedHorizontalSeparationPattern(0, matrix.getWidth() - hspWidth, matrix);
+
+    // Embed vertical separation patterns around the squares.
+    int vspSize = VERTICAL_SEPARATION_PATTERN.length;
+    // Left top corner.
+    embedVerticalSeparationPattern(vspSize, 0, matrix);
+    // Right top corner.
+    embedVerticalSeparationPattern(matrix.getHeight() - vspSize - 1, 0, matrix);
+    // Left bottom corner.
+    embedVerticalSeparationPattern(vspSize, matrix.getHeight() - vspSize,
+        matrix);
+  }
+
+  // Embed position adjustment patterns if need be.
+  private static void maybeEmbedPositionAdjustmentPatterns(int version, ByteMatrix matrix)
+      throws WriterException {
+    if (version < 2) {  // The patterns appear if version >= 2
+      return;
+    }
+    int index = version - 1;
+    int[] coordinates = POSITION_ADJUSTMENT_PATTERN_COORDINATE_TABLE[index];
+    int numCoordinates = POSITION_ADJUSTMENT_PATTERN_COORDINATE_TABLE[index].length;
+    for (int i = 0; i < numCoordinates; ++i) {
+      for (int j = 0; j < numCoordinates; ++j) {
+        int y = coordinates[i];
+        int x = coordinates[j];
+        if (x == -1 || y == -1) {
+          continue;
+        }
+        // If the cell is unset, we embed the position adjustment pattern here.
+        if (isEmpty(matrix.get(x, y))) {
+          // -2 is necessary since the x/y coordinates point to the center of the pattern, not the
+          // left top corner.
+          embedPositionAdjustmentPattern(x - 2, y - 2, matrix);
+        }
+      }
+    }
+  }
+
+}
diff --git a/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/QRCode.java b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/QRCode.java
new file mode 100644
index 000000000..05c818513
--- /dev/null
+++ b/OpenPGP-Keychain/src/com/google/zxing/qrcode/encoder/QRCode.java
@@ -0,0 +1,239 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.qrcode.encoder;
+
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+import com.google.zxing.qrcode.decoder.Mode;
+
+/**
+ * @author satorux@google.com (Satoru Takabayashi) - creator
+ * @author dswitkin@google.com (Daniel Switkin) - ported from C++
+ */
+public final class QRCode {
+
+  public static final int NUM_MASK_PATTERNS = 8;
+
+  private Mode mode;
+  private ErrorCorrectionLevel ecLevel;
+  private int version;
+  private int matrixWidth;
+  private int maskPattern;
+  private int numTotalBytes;
+  private int numDataBytes;
+  private int numECBytes;
+  private int numRSBlocks;
+  private ByteMatrix matrix;
+
+  public QRCode() {
+    mode = null;
+    ecLevel = null;
+    version = -1;
+    matrixWidth = -1;
+    maskPattern = -1;
+    numTotalBytes = -1;
+    numDataBytes = -1;
+    numECBytes = -1;
+    numRSBlocks = -1;
+    matrix = null;
+  }
+
+  // Mode of the QR Code.
+  public Mode getMode() {
+    return mode;
+  }
+
+  // Error correction level of the QR Code.
+  public ErrorCorrectionLevel getECLevel() {
+    return ecLevel;
+  }
+
+  // Version of the QR Code.  The bigger size, the bigger version.
+  public int getVersion() {
+    return version;
+  }
+
+  // ByteMatrix width of the QR Code.
+  public int getMatrixWidth() {
+    return matrixWidth;
+  }
+
+  // Mask pattern of the QR Code.
+  public int getMaskPattern() {
+    return maskPattern;
+  }
+
+  // Number of total bytes in the QR Code.
+  public int getNumTotalBytes() {
+    return numTotalBytes;
+  }
+
+  // Number of data bytes in the QR Code.
+  public int getNumDataBytes() {
+    return numDataBytes;
+  }
+
+  // Number of error correction bytes in the QR Code.
+  public int getNumECBytes() {
+    return numECBytes;
+  }
+
+  // Number of Reedsolomon blocks in the QR Code.
+  public int getNumRSBlocks() {
+    return numRSBlocks;
+  }
+
+  // ByteMatrix data of the QR Code.
+  public ByteMatrix getMatrix() {
+    return matrix;
+  }
+  
+
+  // Return the value of the module (cell) pointed by "x" and "y" in the matrix of the QR Code. They
+  // call cells in the matrix "modules". 1 represents a black cell, and 0 represents a white cell.
+  public int at(int x, int y) {
+    // The value must be zero or one.
+    int value = matrix.get(x, y);
+    if (!(value == 0 || value == 1)) {
+      // this is really like an assert... not sure what better exception to use?
+      throw new RuntimeException("Bad value");
+    }
+    return value;
+  }
+
+  // Checks all the member variables are set properly. Returns true on success. Otherwise, returns
+  // false.
+  public boolean isValid() {
+    return
+        // First check if all version are not uninitialized.
+        mode != null &&
+        ecLevel != null &&
+        version != -1 &&
+        matrixWidth != -1 &&
+        maskPattern != -1 &&
+        numTotalBytes != -1 &&
+        numDataBytes != -1 &&
+        numECBytes != -1 &&
+        numRSBlocks != -1 &&
+        // Then check them in other ways..
+        isValidMaskPattern(maskPattern) &&
+        numTotalBytes == numDataBytes + numECBytes &&
+        // ByteMatrix stuff.
+        matrix != null &&
+        matrixWidth == matrix.getWidth() &&
+        // See 7.3.1 of JISX0510:2004 (p.5).
+        matrix.getWidth() == matrix.getHeight(); // Must be square.
+  }
+
+  // Return debug String.
+  public String toString() {
+    StringBuffer result = new StringBuffer(200);
+    result.append("<<\n");
+    result.append(" mode: ");
+    result.append(mode);
+    result.append("\n ecLevel: ");
+    result.append(ecLevel);
+    result.append("\n version: ");
+    result.append(version);
+    result.append("\n matrixWidth: ");
+    result.append(matrixWidth);
+    result.append("\n maskPattern: ");
+    result.append(maskPattern);
+    result.append("\n numTotalBytes: ");
+    result.append(numTotalBytes);
+    result.append("\n numDataBytes: ");
+    result.append(numDataBytes);
+    result.append("\n numECBytes: ");
+    result.append(numECBytes);
+    result.append("\n numRSBlocks: ");
+    result.append(numRSBlocks);
+    if (matrix == null) {
+      result.append("\n matrix: null\n");
+    } else {
+      result.append("\n matrix:\n");
+      result.append(matrix.toString());
+    }
+    result.append(">>\n");
+    return result.toString();
+  }
+
+  public void setMode(Mode value) {
+    mode = value;
+  }
+
+  public void setECLevel(ErrorCorrectionLevel value) {
+    ecLevel = value;
+  }
+
+  public void setVersion(int value) {
+    version = value;
+  }
+
+  public void setMatrixWidth(int value) {
+    matrixWidth = value;
+  }
+
+  public void setMaskPattern(int value) {
+    maskPattern = value;
+  }
+
+  public void setNumTotalBytes(int value) {
+    numTotalBytes = value;
+  }
+
+  public void setNumDataBytes(int value) {
+    numDataBytes = value;
+  }
+
+  public void setNumECBytes(int value) {
+    numECBytes = value;
+  }
+
+  public void setNumRSBlocks(int value) {
+    numRSBlocks = value;
+  }
+
+  // This takes ownership of the 2D array.
+  public void setMatrix(ByteMatrix value) {
+    matrix = value;
+  }
+
+  // Check if "mask_pattern" is valid.
+  public static boolean isValidMaskPattern(int maskPattern) {
+    return maskPattern >= 0 && maskPattern < NUM_MASK_PATTERNS;
+  }
+
+  // Return true if the all values in the matrix are binary numbers.
+  //
+  // JAVAPORT: This is going to be super expensive and unnecessary, we should not call this in
+  // production. I'm leaving it because it may be useful for testing. It should be removed entirely
+  // if ByteMatrix is changed never to contain a -1.
+  /*
+  private static boolean EverythingIsBinary(final ByteMatrix matrix) {
+    for (int y = 0; y < matrix.height(); ++y) {
+      for (int x = 0; x < matrix.width(); ++x) {
+        int value = matrix.get(y, x);
+        if (!(value == 0 || value == 1)) {
+          // Found non zero/one value.
+          return false;
+        }
+      }
+    }
+    return true;
+  }
+   */
+
+}