// 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(BitVector 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.get_Renamed(xx, y))) { continue; } int bit; if (bitIndex < dataBits.size()) { bit = dataBits.at(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 = 0; } // Skip masking if mask_pattern is -1. if (maskPattern != -1) { if (MaskUtil.getDataMaskBit(maskPattern, xx, y)) { bit ^= 0x1; } } matrix.set_Renamed(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()); } }
// 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); }