1 /** 2 * @file LaplaceDemo.java 3 * @brief Sample code showing how to detect edges using the Laplace operator 4 */ 5 6 import org.opencv.core.*; 7 import org.opencv.highgui.HighGui; 8 import org.opencv.imgcodecs.Imgcodecs; 9 import org.opencv.imgproc.Imgproc; 10 11 class LaplaceDemoRun { 12 run(String[] args)13 public void run(String[] args) { 14 //! [variables] 15 // Declare the variables we are going to use 16 Mat src, src_gray = new Mat(), dst = new Mat(); 17 int kernel_size = 3; 18 int scale = 1; 19 int delta = 0; 20 int ddepth = CvType.CV_16S; 21 String window_name = "Laplace Demo"; 22 //! [variables] 23 24 //! [load] 25 String imageName = ((args.length > 0) ? args[0] : "../data/lena.jpg"); 26 27 src = Imgcodecs.imread(imageName, Imgcodecs.IMREAD_COLOR); // Load an image 28 29 // Check if image is loaded fine 30 if( src.empty() ) { 31 System.out.println("Error opening image"); 32 System.out.println("Program Arguments: [image_name -- default ../data/lena.jpg] \n"); 33 System.exit(-1); 34 } 35 //! [load] 36 37 //! [reduce_noise] 38 // Reduce noise by blurring with a Gaussian filter ( kernel size = 3 ) 39 Imgproc.GaussianBlur( src, src, new Size(3, 3), 0, 0, Core.BORDER_DEFAULT ); 40 //! [reduce_noise] 41 42 //! [convert_to_gray] 43 // Convert the image to grayscale 44 Imgproc.cvtColor( src, src_gray, Imgproc.COLOR_RGB2GRAY ); 45 //! [convert_to_gray] 46 47 /// Apply Laplace function 48 Mat abs_dst = new Mat(); 49 //! [laplacian] 50 Imgproc.Laplacian( src_gray, dst, ddepth, kernel_size, scale, delta, Core.BORDER_DEFAULT ); 51 //! [laplacian] 52 53 //! [convert] 54 // converting back to CV_8U 55 Core.convertScaleAbs( dst, abs_dst ); 56 //! [convert] 57 58 //! [display] 59 HighGui.imshow( window_name, abs_dst ); 60 HighGui.waitKey(0); 61 //! [display] 62 63 System.exit(0); 64 } 65 } 66 67 public class LaplaceDemo { main(String[] args)68 public static void main(String[] args) { 69 // Load the native library. 70 System.loadLibrary(Core.NATIVE_LIBRARY_NAME); 71 new LaplaceDemoRun().run(args); 72 } 73 } 74
