Java Code Examples for org.opencv.core.Core#extractChannel()

public static Mat enhance (Mat image, int level) {
	// color balance
	Mat img1 = Filters.SimplestColorBalance(image, 5);
	img1.convertTo(img1, CvType.CV_8UC1);
	// Perform sRGB to CIE Lab color space conversion
	Mat LabIm1 = new Mat();
	Imgproc.cvtColor(img1, LabIm1, Imgproc.COLOR_BGR2Lab);
	Mat L1 = new Mat();
	Core.extractChannel(LabIm1, L1, 0);
	// apply CLAHE
	Mat[] result = applyCLAHE(LabIm1, L1);
	Mat img2 = result[0];
	Mat L2 = result[1];
	// calculate normalized weight
	Mat w1 = calWeight(img1, L1);
	Mat w2 = calWeight(img2, L2);
	Mat sumW = new Mat();
	Core.add(w1, w2, sumW);
	Core.divide(w1, sumW, w1);
	Core.divide(w2, sumW, w2);
	// merge image1 and image2
	return ImgDecompose.fuseTwoImage(w1, img1, w2, img2, level);
}
 

public static Mat LuminanceWeight(Mat img, Mat L) {
	Mat bCnl = new Mat();
	Core.extractChannel(img, bCnl, 0);
	bCnl.convertTo(bCnl, CvType.CV_32F);
	Mat gCnl = new Mat();
	Core.extractChannel(img, gCnl, 1);
	gCnl.convertTo(gCnl, CvType.CV_32F);
	Mat rCnl = new Mat();
	Core.extractChannel(img, rCnl, 2);
	rCnl.convertTo(rCnl, CvType.CV_32F);
	Mat lum = new Mat(L.rows(), L.cols(), L.type());
	for (int i = 0; i < L.rows(); i++) {
		for (int j = 0; j < L.cols(); j++) {
			double data = Math.sqrt( ( Math.pow(bCnl.get(i, j)[0] / 255.0 - L.get(i, j)[0], 2.0) +
					Math.pow(gCnl.get(i, j)[0] / 255.0 - L.get(i, j)[0], 2.0) +
					Math.pow(rCnl.get(i, j)[0] / 255.0 - L.get(i, j)[0], 2.0) ) / 3 );
			lum.put(i, j, data);
		}
	}
	return lum;
}
 

private static Mat dehazeProcess(Mat img, Mat trans, double[] airlight) {
	Mat balancedImg = Filters.SimplestColorBalance(img, 5);
	Mat bCnl = new Mat();
	Core.extractChannel(balancedImg, bCnl, 0);
	Mat gCnl = new Mat();
	Core.extractChannel(balancedImg, gCnl, 1);
	Mat rCnl = new Mat();
	Core.extractChannel(balancedImg, rCnl, 2);
	// get mean value
	double bMean = Core.mean(bCnl).val[0];
	double gMean = Core.mean(gCnl).val[0];
	double rMean = Core.mean(rCnl).val[0];
	// get transmission map for each channel
	Mat Tb = trans.clone();
	Core.multiply(Tb, new Scalar(Math.max(bMean, Math.max(gMean, rMean)) / bMean * 0.8), Tb);
	Mat Tg = trans.clone();
	Core.multiply(Tg, new Scalar(Math.max(bMean, Math.max(gMean, rMean)) / gMean * 0.9), Tg);
	Mat Tr = trans.clone();
	Core.multiply(Tr, new Scalar(Math.max(bMean, Math.max(gMean, rMean)) / rMean * 0.8), Tr);
	// dehaze by formula
	// blue channel
	Mat bChannel = new Mat();
	Core.subtract(bCnl, new Scalar(airlight[0]), bChannel);
	Core.divide(bChannel, Tb, bChannel);
	Core.add(bChannel, new Scalar(airlight[0]), bChannel);
	// green channel
	Mat gChannel = new Mat();
	Core.subtract(gCnl, new Scalar(airlight[1]), gChannel);
	Core.divide(gChannel, Tg, gChannel);
	Core.add(gChannel, new Scalar(airlight[1]), gChannel);
	// red channel
	Mat rChannel = new Mat();
	Core.subtract(rCnl, new Scalar(airlight[2]), rChannel);
	Core.divide(rChannel, Tr, rChannel);
	Core.add(rChannel, new Scalar(airlight[2]), rChannel);
	Mat dehazed = new Mat();
	Core.merge(new ArrayList<>(Arrays.asList(bChannel, gChannel, rChannel)), dehazed);
	return dehazed;
}
 

public static void main(String[] args) {
	String imgPath = "images/5.jpg";
	Mat image = Imgcodecs.imread(imgPath, Imgcodecs.CV_LOAD_IMAGE_COLOR);
	new ImShow("original").showImage(image);
	// color balance
	Mat img1 = ColorBalance.SimplestColorBalance(image, 5);
	img1.convertTo(img1, CvType.CV_8UC1);
	// Perform sRGB to CIE Lab color space conversion
	Mat LabIm1 = new Mat();
	Imgproc.cvtColor(img1, LabIm1, Imgproc.COLOR_BGR2Lab);
	Mat L1 = new Mat();
	Core.extractChannel(LabIm1, L1, 0);
	// apply CLAHE
	Mat[] result = applyCLAHE(LabIm1, L1);
	Mat img2 = result[0];
	Mat L2 = result[1];
	// calculate normalized weight
	Mat w1 = calWeight(img1, L1);
	Mat w2 = calWeight(img2, L2);
	Mat sumW = new Mat();
	Core.add(w1, w2, sumW);
	Core.divide(w1, sumW, w1);
	Core.divide(w2, sumW, w2);
	// construct the gaussian pyramid for weight
	int level = 5;
	Mat[] weight1 = Pyramid.GaussianPyramid(w1, level);
	Mat[] weight2 = Pyramid.GaussianPyramid(w2, level);
	// construct the laplacian pyramid for input image channel
	img1.convertTo(img1, CvType.CV_32F);
	img2.convertTo(img2, CvType.CV_32F);
	List<Mat> bgr = new ArrayList<Mat>();
	Core.split(img1, bgr);
	Mat[] bCnl1 = Pyramid.LaplacianPyramid(bgr.get(0), level);
	Mat[] gCnl1 = Pyramid.LaplacianPyramid(bgr.get(1), level);
	Mat[] rCnl1 = Pyramid.LaplacianPyramid(bgr.get(2), level);
	bgr.clear();
	Core.split(img2, bgr);
	Mat[] bCnl2 = Pyramid.LaplacianPyramid(bgr.get(0), level);
	Mat[] gCnl2 = Pyramid.LaplacianPyramid(bgr.get(1), level);
	Mat[] rCnl2 = Pyramid.LaplacianPyramid(bgr.get(2), level);
	// fusion process
	Mat[] bCnl = new Mat[level];
	Mat[] gCnl = new Mat[level];
	Mat[] rCnl = new Mat[level];
	for (int i = 0; i < level; i++) {
		Mat cn = new Mat();
		Core.add(bCnl1[i].mul(weight1[i]), bCnl2[i].mul(weight2[i]), cn);
		bCnl[i] = cn.clone();
		Core.add(gCnl1[i].mul(weight1[i]), gCnl2[i].mul(weight2[i]), cn);
		gCnl[i] = cn.clone();
		Core.add(rCnl1[i].mul(weight1[i]), rCnl2[i].mul(weight2[i]), cn);
		rCnl[i] = cn.clone();
	}
	// reconstruct & output
	Mat bChannel = Pyramid.PyramidReconstruct(bCnl);
	Mat gChannel = Pyramid.PyramidReconstruct(gCnl);
	Mat rChannel = Pyramid.PyramidReconstruct(rCnl);
	Mat fusion = new Mat();
	Core.merge(new ArrayList<Mat>(Arrays.asList(bChannel, gChannel, rChannel)), fusion);
	fusion.convertTo(fusion, CvType.CV_8UC1);
	new ImShow("fusion").showImage(fusion);
}
 

protected Mat split(Mat mat, int c) {
    Core.extractChannel(mat, this.split, c);
    return this.split;
}