Tutorial Filter2D

2017-08-24 16:22:27 +01:00
parent 08515281b9
commit a6f5e1f0ca
5 changed files with 295 additions and 85 deletions
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+/**
+ * @file Filter2D_demo.java
+ * @brief Sample code that shows how to implement your own linear filters by using filter2D function
+ */
+
+import org.opencv.core.*;
+import org.opencv.core.Point;
+import org.opencv.highgui.HighGui;
+import org.opencv.imgcodecs.Imgcodecs;
+import org.opencv.imgproc.Imgproc;
+
+class Filter2D_DemoRun {
+
+    public void run(String[] args) {
+        // Declare variables
+        Mat src, dst = new Mat();
+
+        Mat kernel = new Mat();
+        Point anchor;
+        double delta;
+        int ddepth;
+        int kernel_size;
+        String window_name = "filter2D Demo";
+
+        //! [load]
+        String imageName = ((args.length > 0) ? args[0] : "../data/lena.jpg");
+
+        // Load an image
+        src = Imgcodecs.imread(imageName, Imgcodecs.IMREAD_COLOR);
+
+        // Check if image is loaded fine
+        if( src.empty() ) {
+            System.out.println("Error opening image!");
+            System.out.println("Program Arguments: [image_name -- default ../data/lena.jpg] \n");
+            System.exit(-1);
+        }
+        //! [load]
+
+        //! [init_arguments]
+        // Initialize arguments for the filter
+        anchor = new Point( -1, -1);
+        delta = 0.0;
+        ddepth = -1;
+        //! [init_arguments]
+
+        // Loop - Will filter the image with different kernel sizes each 0.5 seconds
+        int ind = 0;
+        while( true )
+        {
+            //! [update_kernel]
+            // Update kernel size for a normalized box filter
+            kernel_size = 3 + 2*( ind%5 );
+            Mat ones = Mat.ones( kernel_size, kernel_size, CvType.CV_32F );
+            Core.multiply(ones, new Scalar(1/(double)(kernel_size*kernel_size)), kernel);
+            //! [update_kernel]
+
+            //! [apply_filter]
+            // Apply filter
+            Imgproc.filter2D(src, dst, ddepth , kernel, anchor, delta, Core.BORDER_DEFAULT );
+            //! [apply_filter]
+            HighGui.imshow( window_name, dst );
+
+            int c = HighGui.waitKey(500);
+            // Press 'ESC' to exit the program
+            if( c == 27 )
+            { break; }
+
+            ind++;
+        }
+
+        System.exit(0);
+    }
+}
+
+public class Filter2D_Demo {
+    public static void main(String[] args) {
+        // Load the native library.
+        System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
+        new Filter2D_DemoRun().run(args);
+    }
+}