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) { throw new WriterException("should not happen but we got: " + bits.getSize()); } }
// Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses // 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap). private static BitMatrix renderResult(QRCode code, int width, int height, int quietZone) { ByteMatrix input = code.getMatrix(); if (input == null) { throw new IllegalStateException(); } int inputWidth = input.getWidth(); int inputHeight = input.getHeight(); int qrWidth = inputWidth + (quietZone << 1); int qrHeight = inputHeight + (quietZone << 1); int outputWidth = Math.max(width, qrWidth); int outputHeight = Math.max(height, qrHeight); int multiple = Math.min(outputWidth / qrWidth, outputHeight / qrHeight); // Padding includes both the quiet zone and the extra white pixels to accommodate the requested // dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone. // If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will // handle all the padding from 100x100 (the actual QR) up to 200x160. int leftPadding = (outputWidth - (inputWidth * multiple)) / 2; int topPadding = (outputHeight - (inputHeight * multiple)) / 2; BitMatrix output = new BitMatrix(outputWidth, outputHeight); for (int inputY = 0, outputY = topPadding; inputY < inputHeight; inputY++, outputY += multiple) { // Write the contents of this row of the barcode for (int inputX = 0, outputX = leftPadding; inputX < inputWidth; inputX++, outputX += multiple) { if (input.get(inputX, inputY) == 1) { output.setRegion(outputX, outputY, multiple, multiple); } } } return output; }