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- /*
- * 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 ZXing.Common;
-
- namespace ZXing.QrCode.Internal
- {
- /// <summary>
- ///
- /// </summary>
- /// <author>
- /// satorux@google.com (Satoru Takabayashi) - creator
- /// </author>
- public static class MatrixUtil
- {
- private static readonly int[][] POSITION_DETECTION_PATTERN = new int[][]
- {
- new int[] { 1, 1, 1, 1, 1, 1, 1 },
- new int[] { 1, 0, 0, 0, 0, 0, 1 },
- new int[] { 1, 0, 1, 1, 1, 0, 1 },
- new int[] { 1, 0, 1, 1, 1, 0, 1 },
- new int[] { 1, 0, 1, 1, 1, 0, 1 },
- new int[] { 1, 0, 0, 0, 0, 0, 1 },
- new int[] { 1, 1, 1, 1, 1, 1, 1 }
- };
-
- private static readonly int[][] POSITION_ADJUSTMENT_PATTERN = new int[][]
- {
- new int[] { 1, 1, 1, 1, 1 },
- new int[] { 1, 0, 0, 0, 1 },
- new int[] { 1, 0, 1, 0, 1 },
- new int[] { 1, 0, 0, 0, 1 },
- new int[] { 1, 1, 1, 1, 1 }
- };
-
- // From Appendix E. Table 1, JIS0510X:2004 (p 71). The table was double-checked by komatsu.
- private static readonly int[][] POSITION_ADJUSTMENT_PATTERN_COORDINATE_TABLE = new int[][]
- {
- new int[] { -1, -1, -1, -1, -1, -1, -1 },
- new int[] { 6, 18, -1, -1, -1, -1, -1 },
- new int[] { 6, 22, -1, -1, -1, -1, -1 },
- new int[] { 6, 26, -1, -1, -1, -1, -1 },
- new int[] { 6, 30, -1, -1, -1, -1, -1 },
- new int[] { 6, 34, -1, -1, -1, -1, -1 },
- new int[] { 6, 22, 38, -1, -1, -1, -1 },
- new int[] { 6, 24, 42, -1, -1, -1, -1 },
- new int[] { 6, 26, 46, -1, -1, -1, -1 },
- new int[] { 6, 28, 50, -1, -1, -1, -1 },
- new int[] { 6, 30, 54, -1, -1, -1, -1 },
- new int[] { 6, 32, 58, -1, -1, -1, -1 },
- new int[] { 6, 34, 62, -1, -1, -1, -1 },
- new int[] { 6, 26, 46, 66, -1, -1, -1 },
- new int[] { 6, 26, 48, 70, -1, -1, -1 },
- new int[] { 6, 26, 50, 74, -1, -1, -1 },
- new int[] { 6, 30, 54, 78, -1, -1, -1 },
- new int[] { 6, 30, 56, 82, -1, -1, -1 },
- new int[] { 6, 30, 58, 86, -1, -1, -1 },
- new int[] { 6, 34, 62, 90, -1, -1, -1 },
- new int[] { 6, 28, 50, 72, 94, -1, -1 },
- new int[] { 6, 26, 50, 74, 98, -1, -1 },
- new int[] { 6, 30, 54, 78, 102, -1, -1 },
- new int[] { 6, 28, 54, 80, 106, -1, -1 },
- new int[] { 6, 32, 58, 84, 110, -1, -1 },
- new int[] { 6, 30, 58, 86, 114, -1, -1 },
- new int[] { 6, 34, 62, 90, 118, -1, -1 },
- new int[] { 6, 26, 50, 74, 98, 122, -1 },
- new int[] { 6, 30, 54, 78, 102, 126, -1 },
- new int[] { 6, 26, 52, 78, 104, 130, -1 },
- new int[] { 6, 30, 56, 82, 108, 134, -1 },
- new int[] { 6, 34, 60, 86, 112, 138, -1 },
- new int[] { 6, 30, 58, 86, 114, 142, -1 },
- new int[] { 6, 34, 62, 90, 118, 146, -1 },
- new int[] { 6, 30, 54, 78, 102, 126, 150 },
- new int[] { 6, 24, 50, 76, 102, 128, 154 },
- new int[] { 6, 28, 54, 80, 106, 132, 158 },
- new int[] { 6, 32, 58, 84, 110, 136, 162 },
- new int[] { 6, 26, 54, 82, 110, 138, 166 },
- new int[] { 6, 30, 58, 86, 114, 142, 170 }
- };
-
- // Type info cells at the left top corner.
- private static readonly int[][] TYPE_INFO_COORDINATES = new int[][]
- {
- new int[] { 8, 0 },
- new int[] { 8, 1 },
- new int[] { 8, 2 },
- new int[] { 8, 3 },
- new int[] { 8, 4 },
- new int[] { 8, 5 },
- new int[] { 8, 7 },
- new int[] { 8, 8 },
- new int[] { 7, 8 },
- new int[] { 5, 8 },
- new int[] { 4, 8 },
- new int[] { 3, 8 },
- new int[] { 2, 8 },
- new int[] { 1, 8 },
- new int[] { 0, 8 }
- };
-
- // From Appendix D in JISX0510:2004 (p. 67)
- private const int VERSION_INFO_POLY = 0x1f25; // 1 1111 0010 0101
-
- // From Appendix C in JISX0510:2004 (p.65).
- private const int TYPE_INFO_POLY = 0x537;
- private const int TYPE_INFO_MASK_PATTERN = 0x5412;
-
- /// <summary>
- /// Set all cells to 2. 2 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.
- /// </summary>
- /// <param name="matrix">The matrix.</param>
- public static void clearMatrix(ByteMatrix matrix)
- {
- matrix.clear(2);
- }
-
- /// <summary>
- /// Build 2D matrix of QR Code from "dataBits" with "ecLevel", "version" and "getMaskPattern". On
- /// success, store the result in "matrix" and return true.
- /// </summary>
- /// <param name="dataBits">The data bits.</param>
- /// <param name="ecLevel">The ec level.</param>
- /// <param name="version">The version.</param>
- /// <param name="maskPattern">The mask pattern.</param>
- /// <param name="matrix">The matrix.</param>
- public static void buildMatrix(BitArray dataBits, ErrorCorrectionLevel ecLevel, Version version, int maskPattern, ByteMatrix matrix)
- {
- 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);
- }
-
- /// <summary>
- /// 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
- /// </summary>
- /// <param name="version">The version.</param>
- /// <param name="matrix">The matrix.</param>
- public static void embedBasicPatterns(Version version, ByteMatrix matrix)
- {
- // 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);
- }
-
- /// <summary>
- /// Embed type information. On success, modify the matrix.
- /// </summary>
- /// <param name="ecLevel">The ec level.</param>
- /// <param name="maskPattern">The mask pattern.</param>
- /// <param name="matrix">The matrix.</param>
- public static void embedTypeInfo(ErrorCorrectionLevel ecLevel, int maskPattern, ByteMatrix matrix)
- {
- BitArray typeInfoBits = new BitArray();
- makeTypeInfoBits(ecLevel, maskPattern, typeInfoBits);
-
- for (int i = 0; i < typeInfoBits.Size; ++i)
- {
- // Place bits in LSB to MSB order. LSB (least significant bit) is the last value in
- // "typeInfoBits".
- int bit = typeInfoBits[typeInfoBits.Size - 1 - i] ? 1 : 0;
-
- // 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[x1, y1] = bit;
-
- if (i < 8)
- {
- // Right top corner.
- int x2 = matrix.Width - i - 1;
- int y2 = 8;
- matrix[x2, y2] = bit;
- }
- else
- {
- // Left bottom corner.
- int x2 = 8;
- int y2 = matrix.Height - 7 + (i - 8);
- matrix[x2, y2] = bit;
- }
- }
- }
-
- /// <summary>
- /// 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.
- /// </summary>
- /// <param name="version">The version.</param>
- /// <param name="matrix">The matrix.</param>
- public static void maybeEmbedVersionInfo(Version version, ByteMatrix matrix)
- {
- if (version.VersionNumber < 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.
- var bit = versionInfoBits[bitIndex] ? 1 : 0;
- bitIndex--;
- // Left bottom corner.
- matrix[i, matrix.Height - 11 + j] = bit;
- // Right bottom corner.
- matrix[matrix.Height - 11 + j, i] = bit;
- }
- }
- }
-
- /// <summary>
- /// 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.
- /// </summary>
- /// <param name="dataBits">The data bits.</param>
- /// <param name="maskPattern">The mask pattern.</param>
- /// <param name="matrix">The matrix.</param>
- public static void embedDataBits(BitArray dataBits, int maskPattern, ByteMatrix matrix)
- {
- int bitIndex = 0;
- int direction = -1;
- // Start from the right bottom cell.
- int x = matrix.Width - 1;
- int y = matrix.Height - 1;
- while (x > 0)
- {
- // Skip the vertical timing pattern.
- if (x == 6)
- {
- x -= 1;
- }
- while (y >= 0 && y < matrix.Height)
- {
- for (int i = 0; i < 2; ++i)
- {
- int xx = x - i;
- // Skip the cell if it's not empty.
- if (!isEmpty(matrix[xx, y]))
- {
- continue;
- }
- int bit;
- if (bitIndex < dataBits.Size)
- {
- bit = dataBits[bitIndex] ? 1 : 0;
- ++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 = 0;
- }
-
- // Skip masking if mask_pattern is -1.
- if (maskPattern != -1)
- {
- if (MaskUtil.getDataMaskBit(maskPattern, xx, y))
- {
- bit ^= 0x1;
- }
- }
- matrix[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.Size)
- {
- throw new WriterException("Not all bits consumed: " + bitIndex + '/' + dataBits.Size);
- }
- }
-
- /// <summary>
- /// 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
- /// </summary>
- /// <param name="value_Renamed">The value_ renamed.</param>
- /// <returns></returns>
- public static int findMSBSet(int value_Renamed)
- {
- int numDigits = 0;
- while (value_Renamed != 0)
- {
- value_Renamed = (int)((uint)value_Renamed >> 1);
- ++numDigits;
- }
- return numDigits;
- }
-
- /// <summary>
- /// 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^2 + x^1
- /// 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.
- /// </summary>
- /// <param name="value">The value.</param>
- /// <param name="poly">The poly.</param>
- /// <returns></returns>
- 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;
- }
-
- /// <summary>
- /// 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.
- /// </summary>
- /// <param name="ecLevel">The ec level.</param>
- /// <param name="maskPattern">The mask pattern.</param>
- /// <param name="bits">The bits.</param>
- public static void makeTypeInfoBits(ErrorCorrectionLevel ecLevel, int maskPattern, BitArray bits)
- {
- if (!QRCode.isValidMaskPattern(maskPattern))
- {
- throw new WriterException("Invalid mask pattern");
- }
- int typeInfo = (ecLevel.Bits << 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.Size != 15)
- {
- // Just in case.
- throw new WriterException("should not happen but we got: " + bits.Size);
- }
- }
-
- /// <summary>
- /// 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.
- /// </summary>
- /// <param name="version">The version.</param>
- /// <param name="bits">The bits.</param>
- public static void makeVersionInfoBits(Version version, BitArray bits)
- {
- bits.appendBits(version.VersionNumber, 6);
- int bchCode = calculateBCHCode(version.VersionNumber, VERSION_INFO_POLY);
- bits.appendBits(bchCode, 12);
-
- if (bits.Size != 18)
- {
- // Just in case.
- throw new WriterException("should not happen but we got: " + bits.Size);
- }
- }
-
- /// <summary>
- /// Check if "value" is empty.
- /// </summary>
- /// <param name="value">The value.</param>
- /// <returns>
- /// <c>true</c> if the specified value is empty; otherwise, <c>false</c>.
- /// </returns>
- private static bool isEmpty(int value)
- {
- return value == 2;
- }
-
- private static void embedTimingPatterns(ByteMatrix matrix)
- {
- // -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.Width - 8; ++i)
- {
- int bit = (i + 1) % 2;
- // Horizontal line.
- if (isEmpty(matrix[i, 6]))
- {
- matrix[i, 6] = bit;
- }
- // Vertical line.
- if (isEmpty(matrix[6, i]))
- {
- matrix[6, i] = bit;
- }
- }
- }
-
- /// <summary>
- /// Embed the lonely dark dot at left bottom corner. JISX0510:2004 (p.46)
- /// </summary>
- /// <param name="matrix">The matrix.</param>
- private static void embedDarkDotAtLeftBottomCorner(ByteMatrix matrix)
- {
- if (matrix[8, matrix.Height - 8] == 0)
- {
- throw new WriterException();
- }
- matrix[8, matrix.Height - 8] = 1;
- }
-
- private static void embedHorizontalSeparationPattern(int xStart, int yStart, ByteMatrix matrix)
- {
- for (int x = 0; x < 8; ++x)
- {
- if (!isEmpty(matrix[xStart + x, yStart]))
- {
- throw new WriterException();
- }
- matrix[xStart + x, yStart] = 0;
- }
- }
-
- private static void embedVerticalSeparationPattern(int xStart, int yStart, ByteMatrix matrix)
- {
- for (int y = 0; y < 7; ++y)
- {
- if (!isEmpty(matrix[xStart, yStart + y]))
- {
- throw new WriterException();
- }
- matrix[xStart, yStart + y] = 0;
- }
- }
-
- /// <summary>
- /// 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.
- /// </summary>
- /// <param name="xStart">The x start.</param>
- /// <param name="yStart">The y start.</param>
- /// <param name="matrix">The matrix.</param>
- private static void embedPositionAdjustmentPattern(int xStart, int yStart, ByteMatrix matrix)
- {
- for (int y = 0; y < 5; ++y)
- {
- for (int x = 0; x < 5; ++x)
- {
- matrix[xStart + x, yStart + y] = POSITION_ADJUSTMENT_PATTERN[y][x];
- }
- }
- }
-
- private static void embedPositionDetectionPattern(int xStart, int yStart, ByteMatrix matrix)
- {
- for (int y = 0; y < 7; ++y)
- {
- for (int x = 0; x < 7; ++x)
- {
- matrix[xStart + x, yStart + y] = POSITION_DETECTION_PATTERN[y][x];
- }
- }
- }
-
- /// <summary>
- /// Embed position detection patterns and surrounding vertical/horizontal separators.
- /// </summary>
- /// <param name="matrix">The matrix.</param>
- private static void embedPositionDetectionPatternsAndSeparators(ByteMatrix matrix)
- {
- // 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.Width - pdpWidth, 0, matrix);
- // Left bottom corner.
- embedPositionDetectionPattern(0, matrix.Width - pdpWidth, matrix);
-
- // Embed horizontal separation patterns around the squares.
- const int hspWidth = 8;
- // Left top corner.
- embedHorizontalSeparationPattern(0, hspWidth - 1, matrix);
- // Right top corner.
- embedHorizontalSeparationPattern(matrix.Width - hspWidth, hspWidth - 1, matrix);
- // Left bottom corner.
- embedHorizontalSeparationPattern(0, matrix.Width - hspWidth, matrix);
-
- // Embed vertical separation patterns around the squares.
- const int vspSize = 7;
- // Left top corner.
- embedVerticalSeparationPattern(vspSize, 0, matrix);
- // Right top corner.
- embedVerticalSeparationPattern(matrix.Height - vspSize - 1, 0, matrix);
- // Left bottom corner.
- embedVerticalSeparationPattern(vspSize, matrix.Height - vspSize, matrix);
- }
-
- /// <summary>
- /// Embed position adjustment patterns if need be.
- /// </summary>
- /// <param name="version">The version.</param>
- /// <param name="matrix">The matrix.</param>
- private static void maybeEmbedPositionAdjustmentPatterns(Version version, ByteMatrix matrix)
- {
- if (version.VersionNumber < 2)
- {
- // The patterns appear if version >= 2
- return;
- }
- int index = version.VersionNumber - 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[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);
- }
- }
- }
- }
- }
- }
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