Java tutorial
package usefull; //******************************************************** //Example : displaying an image from file //Author : Toby Breckon, toby.breckon@durham.ac.uk //Copyright (c) 2015 Durham University //License : LGPL - http://www.gnu.org/licenses/lgpl.html //******************************************************** //import required OpenCV components import org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.highgui.Highgui; //******************************************************** public class ColourQuery { public static void main(String[] args) { // load the Core OpenCV library by name System.loadLibrary(Core.NATIVE_LIBRARY_NAME); // load an image from file (read and decode JPEG file) Mat inputImage = Highgui.imread("files/lena1.png"); // create a display window using an Imshow object Imshow ims1 = new Imshow("My Image"); // display some colour values (note the BGR colour channel order) double[] bgr = inputImage.get(0, 0); System.out.println("colour @ (0,0) = B: " + bgr[0] + " G: " + bgr[1] + " R: " + bgr[2]); bgr = inputImage.get(50, 50); System.out.println("colour @ (50,50) = B: " + bgr[0] + " G: " + bgr[1] + " R: " + bgr[2]); bgr = inputImage.get(100, 25); System.out.println("colour @ (100,25) = B: " + bgr[0] + " G: " + bgr[1] + " R: " + bgr[2]); bgr = inputImage.get(17, 234); System.out.println("colour @ (17,234) = B: " + bgr[0] + " G: " + bgr[1] + " R: " + bgr[2]); // set some pixel values to blue (i.e. BGR = (255,0,0) double[] colour = new double[3]; colour[0] = 255; colour[1] = 0; colour[2] = 0; inputImage.put(25, 25, colour); inputImage.put(25, 24, colour); inputImage.put(25, 23, colour); inputImage.put(25, 22, colour); // ... // display image ims1.showImage(inputImage); } } //********************************************************