zxing/csharp/qrcode/encoder/Encoder.cs
srowen d4efd44fb0 New C# port from Suraj Supekar
git-svn-id: https://zxing.googlecode.com/svn/trunk@1202 59b500cc-1b3d-0410-9834-0bbf25fbcc57
2010-02-05 19:52:53 +00:00

642 lines
23 KiB
C#
Executable file

/*
* 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.
*/
using System;
using WriterException = com.google.zxing.WriterException;
using EncodeHintType = com.google.zxing.EncodeHintType;
using ByteArray = com.google.zxing.common.ByteArray;
using ByteMatrix = com.google.zxing.common.ByteMatrix;
using CharacterSetECI = com.google.zxing.common.CharacterSetECI;
using GF256 = com.google.zxing.common.reedsolomon.GF256;
using ReedSolomonEncoder = com.google.zxing.common.reedsolomon.ReedSolomonEncoder;
using ErrorCorrectionLevel = com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
using Mode = com.google.zxing.qrcode.decoder.Mode;
using Version = com.google.zxing.qrcode.decoder.Version;
namespace com.google.zxing.qrcode.encoder
{
/// <author> satorux@google.com (Satoru Takabayashi) - creator
/// </author>
/// <author> dswitkin@google.com (Daniel Switkin) - ported from C++
/// </author>
/// <author>www.Redivivus.in (suraj.supekar@redivivus.in) - Ported from ZXING Java Source
/// </author>
public sealed class Encoder
{
// The original table is defined in the table 5 of JISX0510:2004 (p.19).
//UPGRADE_NOTE: Final was removed from the declaration of 'ALPHANUMERIC_TABLE'. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1003'"
private static readonly int[] ALPHANUMERIC_TABLE = new int[]{- 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, - 1, 36, - 1, - 1, - 1, 37, 38, - 1, - 1, - 1, - 1, 39, 40, - 1, 41, 42, 43, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 44, - 1, - 1, - 1, - 1, - 1, - 1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, - 1, - 1, - 1, - 1, - 1};
internal const System.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;
}
/// <summary> 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.
/// </summary>
public static void encode(System.String content, ErrorCorrectionLevel ecLevel, QRCode qrCode)
{
encode(content, ecLevel, null, qrCode);
}
public static void encode(System.String content, ErrorCorrectionLevel ecLevel, System.Collections.Hashtable hints, QRCode qrCode)
{
System.String encoding = hints == null?null:(System.String) hints[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.Version, mode, headerAndDataBits);
headerAndDataBits.appendBitVector(dataBits);
// Step 5: Terminate the bits properly.
terminateBits(qrCode.NumDataBytes, headerAndDataBits);
// Step 6: Interleave data bits with error correction code.
BitVector finalBits = new BitVector();
interleaveWithECBytes(headerAndDataBits, qrCode.NumTotalBytes, qrCode.NumDataBytes, qrCode.NumRSBlocks, finalBits);
// Step 7: Choose the mask pattern and set to "qrCode".
ByteMatrix matrix = new ByteMatrix(qrCode.MatrixWidth, qrCode.MatrixWidth);
qrCode.MaskPattern = chooseMaskPattern(finalBits, qrCode.ECLevel, qrCode.Version, matrix);
// Step 8. Build the matrix and set it to "qrCode".
MatrixUtil.buildMatrix(finalBits, qrCode.ECLevel, qrCode.Version, qrCode.MaskPattern, matrix);
qrCode.Matrix = matrix;
// Step 9. Make sure we have a valid QR Code.
if (!qrCode.Valid)
{
throw new WriterException("Invalid QR code: " + qrCode.ToString());
}
}
/// <returns> the code point of the table used in alphanumeric mode or
/// -1 if there is no corresponding code in the table.
/// </returns>
internal static int getAlphanumericCode(int code)
{
if (code < ALPHANUMERIC_TABLE.Length)
{
return ALPHANUMERIC_TABLE[code];
}
return - 1;
}
public static Mode chooseMode(System.String content)
{
return chooseMode(content, null);
}
/// <summary> 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}.
/// </summary>
public static Mode chooseMode(System.String content, System.String encoding)
{
if ("Shift_JIS".Equals(encoding))
{
// Choose Kanji mode if all input are double-byte characters
return isOnlyDoubleByteKanji(content)?Mode.KANJI:Mode.BYTE;
}
bool hasNumeric = false;
bool hasAlphanumeric = false;
for (int i = 0; i < content.Length; ++i)
{
char c = content[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 bool isOnlyDoubleByteKanji(System.String content)
{
sbyte[] bytes;
try
{
//UPGRADE_TODO: Method 'java.lang.String.getBytes' was converted to 'System.Text.Encoding.GetEncoding(string).GetBytes(string)' which has a different behavior. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1073_javalangStringgetBytes_javalangString'"
bytes = SupportClass.ToSByteArray(System.Text.Encoding.GetEncoding("Shift_JIS").GetBytes(content));
}
catch (System.IO.IOException 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(BitVector bits, ErrorCorrectionLevel ecLevel, int version, ByteMatrix matrix)
{
int minPenalty = System.Int32.MaxValue; // 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;
}
/// <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?)");
}
/// <summary> Terminate bits as described in 8.4.8 and 8.4.9 of JISX0510:2004 (p.24).</summary>
internal static void terminateBits(int numDataBytes, BitVector bits)
{
int capacity = numDataBytes << 3;
if (bits.size() > capacity)
{
throw new WriterException("data bits cannot fit in the QR Code" + bits.size() + " > " + capacity);
}
// Append termination bits. See 8.4.8 of JISX0510:2004 (p.24) for details.
// TODO: srowen says we can remove this for loop, since the 4 terminator bits are optional if
// the last byte has less than 4 bits left. So it amounts to padding the last byte with zeroes
// either way.
for (int i = 0; i < 4 && bits.size() < capacity; ++i)
{
bits.appendBit(0);
}
int numBitsInLastByte = bits.size() % 8;
// If the last byte isn't 8-bit aligned, we'll add padding bits.
if (numBitsInLastByte > 0)
{
int numPaddingBits = 8 - numBitsInLastByte;
for (int i = 0; i < numPaddingBits; ++i)
{
bits.appendBit(0);
}
}
// Should be 8-bit aligned here.
if (bits.size() % 8 != 0)
{
throw new WriterException("Number of bits is not a multiple of 8");
}
// If we have more space, we'll fill the space with padding patterns defined in 8.4.9 (p.24).
int numPaddingBytes = numDataBytes - bits.sizeInBytes();
for (int i = 0; i < numPaddingBytes; ++i)
{
if (i % 2 == 0)
{
bits.appendBits(0xec, 8);
}
else
{
bits.appendBits(0x11, 8);
}
}
if (bits.size() != capacity)
{
throw new WriterException("Bits size does not equal capacity");
}
}
/// <summary> 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)
/// </summary>
internal static void getNumDataBytesAndNumECBytesForBlockID(int numTotalBytes, int numDataBytes, int numRSBlocks, int blockID, int[] numDataBytesInBlock, int[] numECBytesInBlock)
{
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;
}
}
/// <summary> 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.
/// </summary>
internal static void interleaveWithECBytes(BitVector bits, int numTotalBytes, int numDataBytes, int numRSBlocks, BitVector result)
{
// "bits" must have "getNumDataBytes" bytes of data.
if (bits.sizeInBytes() != 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.
System.Collections.ArrayList blocks = System.Collections.ArrayList.Synchronized(new System.Collections.ArrayList(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);
ByteArray dataBytes = new ByteArray();
dataBytes.set_Renamed(bits.Array, dataBytesOffset, numDataBytesInBlock[0]);
ByteArray ecBytes = generateECBytes(dataBytes, numEcBytesInBlock[0]);
blocks.Add(new BlockPair(dataBytes, ecBytes));
maxNumDataBytes = System.Math.Max(maxNumDataBytes, dataBytes.size());
maxNumEcBytes = System.Math.Max(maxNumEcBytes, ecBytes.size());
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.Count; ++j)
{
ByteArray dataBytes = ((BlockPair) blocks[j]).DataBytes;
if (i < dataBytes.size())
{
result.appendBits(dataBytes.at(i), 8);
}
}
}
// Then, place error correction blocks.
for (int i = 0; i < maxNumEcBytes; ++i)
{
for (int j = 0; j < blocks.Count; ++j)
{
ByteArray ecBytes = ((BlockPair) blocks[j]).ErrorCorrectionBytes;
if (i < ecBytes.size())
{
result.appendBits(ecBytes.at(i), 8);
}
}
}
if (numTotalBytes != result.sizeInBytes())
{
// Should be same.
throw new WriterException("Interleaving error: " + numTotalBytes + " and " + result.sizeInBytes() + " differ.");
}
}
internal static ByteArray generateECBytes(ByteArray dataBytes, int numEcBytesInBlock)
{
int numDataBytes = dataBytes.size();
int[] toEncode = new int[numDataBytes + numEcBytesInBlock];
for (int i = 0; i < numDataBytes; i++)
{
toEncode[i] = dataBytes.at(i);
}
new ReedSolomonEncoder(GF256.QR_CODE_FIELD).encode(toEncode, numEcBytesInBlock);
ByteArray ecBytes = new ByteArray(numEcBytesInBlock);
for (int i = 0; i < numEcBytesInBlock; i++)
{
ecBytes.set_Renamed(i, toEncode[numDataBytes + i]);
}
return ecBytes;
}
/// <summary> Append mode info. On success, store the result in "bits".</summary>
internal static void appendModeInfo(Mode mode, BitVector bits)
{
bits.appendBits(mode.Bits, 4);
}
/// <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);
}
/// <summary> Append "bytes" in "mode" mode (encoding) into "bits". On success, store the result in "bits".</summary>
internal static void appendBytes(System.String content, Mode mode, BitVector bits, System.String encoding)
{
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);
}
}
internal static void appendNumericBytes(System.String content, BitVector bits)
{
int length = content.Length;
int i = 0;
while (i < length)
{
int num1 = content[i] - '0';
if (i + 2 < length)
{
// Encode three numeric letters in ten bits.
int num2 = content[i + 1] - '0';
int num3 = content[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[i + 1] - '0';
bits.appendBits(num1 * 10 + num2, 7);
i += 2;
}
else
{
// Encode one numeric letter in four bits.
bits.appendBits(num1, 4);
i++;
}
}
}
internal static void appendAlphanumericBytes(System.String content, BitVector bits)
{
int length = content.Length;
int i = 0;
while (i < length)
{
int code1 = getAlphanumericCode(content[i]);
if (code1 == - 1)
{
throw new WriterException();
}
if (i + 1 < length)
{
int code2 = getAlphanumericCode(content[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++;
}
}
}
internal static void append8BitBytes(System.String content, BitVector bits, System.String encoding)
{
sbyte[] bytes;
try
{
//UPGRADE_TODO: Method 'java.lang.String.getBytes' was converted to 'System.Text.Encoding.GetEncoding(string).GetBytes(string)' which has a different behavior. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1073_javalangStringgetBytes_javalangString'"
bytes = SupportClass.ToSByteArray(System.Text.Encoding.GetEncoding(encoding).GetBytes(content));
}
catch (System.IO.IOException uee)
{
//UPGRADE_TODO: The equivalent in .NET for method 'java.lang.Throwable.toString' may return a different value. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1043'"
throw new WriterException(uee.ToString());
}
for (int i = 0; i < bytes.Length; ++i)
{
bits.appendBits(bytes[i], 8);
}
}
internal static void appendKanjiBytes(System.String content, BitVector bits)
{
sbyte[] bytes;
try
{
//UPGRADE_TODO: Method 'java.lang.String.getBytes' was converted to 'System.Text.Encoding.GetEncoding(string).GetBytes(string)' which has a different behavior. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1073_javalangStringgetBytes_javalangString'"
bytes = SupportClass.ToSByteArray(System.Text.Encoding.GetEncoding("Shift_JIS").GetBytes(content));
}
catch (System.IO.IOException uee)
{
//UPGRADE_TODO: The equivalent in .NET for method 'java.lang.Throwable.toString' may return a different value. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1043'"
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(CharacterSetECI eci, BitVector bits)
{
bits.appendBits(Mode.ECI.Bits, 4);
// This is correct for values up to 127, which is all we need now.
bits.appendBits(eci.Value, 8);
}
}
}