/** * 基于离散余弦变换（DCT）的水印编码功能 * @param inputImgPath * @param textWatermark * @param outputImgPath */ public static void dctWaterMarkEncode(String inputImgPath, String textWatermark, String outputImgPath) { // 读取图像 Mat src = OpenCVUtils.imread(inputImgPath, org.opencv.core.CvType.CV_8S);
List<Mat> channel = new ArrayList<>(3); List<Mat> newChannel = new ArrayList<>(3); org.opencv.core.Core.split(src, channel);
for (int i = 0; i < 3; i++) { Mat com = dctWaterMarkDCT(channel.get(i)).clone(); // you can set different location in 'new Point()'， just copy putText method putText(com, textWatermark, new Point(com.cols() / 3, com.rows() / 2), FONT_HERSHEY_COMPLEX, 5.0, new Scalar(2, 2, 2, 0), 20, LINE_AA, false); idct(com, com); newChannel.add(i, com); }
Mat res = new Mat(); org.opencv.core.Core.merge(newChannel, res);
if (res.rows() != src.rows() || res.cols() != src.cols()) { res = new Mat(res, new Rect(0, 0, src.width(), src.height())); }
org.opencv.imgcodecs.Imgcodecs.imwrite(outputImgPath, res); }
/** * 基于离散余弦变换（DCT）的水印解码功能 * @param inputImgPath * @param outputImgPath */ public static void dctWaterMarkDecode(String inputImgPath, String outputImgPath) { Mat dctWaterMark = dctWaterMarkDCT(OpenCVUtils.imread(inputImgPath, CV_8U)); dctWaterMark.convertTo(dctWaterMark, COLOR_RGB2HSV); inRange(dctWaterMark, new Scalar(0, 0, 0, 0), new Scalar(16, 16, 16, 0), dctWaterMark); org.opencv.core.Core.normalize(dctWaterMark, dctWaterMark, 0, 255, NORM_MINMAX, CV_8UC1); org.opencv.imgcodecs.Imgcodecs.imwrite(outputImgPath, dctWaterMark); }
private static Mat dctWaterMarkDCT(Mat src) { if ((src.cols() & 1) != 0) { copyMakeBorder(src, src, 0, 0, 0, 1, BORDER_CONSTANT, Scalar.all(0)); } if ((src.rows() & 1) != 0) { copyMakeBorder(src, src, 0, 1, 0, 0, BORDER_CONSTANT, Scalar.all(0)); } src.convertTo(src, CV_32F); dct(src, src); return src; }
评论