Geometric Shapes to Images

Problem Description

How to draw geometric shapes to an image using java.

Solution

Following is the program to draw geometric shapes to an image using java.

import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.core.Point;
import org.opencv.core.Scalar;

import org.opencv.imgcodecs.Imgcodecs;
import org.opencv.imgproc.Imgproc;

public class DrawingshapesOnImage {
   public static void main(String args[]) {
      
      //Loading the OpenCV core library
      System.loadLibrary( Core.NATIVE_LIBRARY_NAME );

      //Reading the Image from the file and storing it in to a Matrix object
      String file = "C:/opencv/logo.jpg";
      Mat matrix = Imgcodecs.imread(file);

      /*
         //Drawing an Ellipse
         Imgproc.ellipse(matrix,     //Matrix obj of the image
         new RotatedRect( new Point(20, 150),new Size(260, 180), 180 ),
            //RotatedRect(Point c, Size s, double a)
            new Scalar(0, 0, 255),     //Scalar object for color
            10);                       //Thickness of the line 
      */

      //Drawing a Rectangle
      Imgproc.rectangle(matrix,      //Matrix obj of the image
         new Point(10, 10),          //p1
         new Point(390, 390),        //p2
         new Scalar(0, 100, 255),    //Scalar object for color
         5);                         //Thickness of the line

      //Writing image
      Imgcodecs.imwrite("C:/opencv/drawingShapesOnImage.jpg", matrix);
      System.out.println("Image processed");
   }
}

Input

Output