Create Custom Color Maps in Java Using OpenCV

The applyColorMap() method of the Imgproc class applies specified color map to the given image. This method accepts three parameters −

• Two Mat objects representing the source and destination images.

• An integer variable representing the type of the color map to be applied.

You can pass any of the following as color map value to this method.

COLORMAP_AUTUMN, COLORMAP_BONE, COLORMAP_COOL, COLORMAP_HOT, COLORMAP_HSV, COLORMAP_JET, COLORMAP_OCEAN , COLORMAP_PARULA, COLORMAP_PINK, COLORMAP_RAINBOW, COLORMAP_SPRING, COLORMAP_SUMMER, COLORMAP_WINTER.

Example

import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.imgcodecs.Imgcodecs;
import org.opencv.imgproc.Imgproc;
public class CustomColorMaps {
   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 ="D:\images\cat.jpg";
      Mat src = Imgcodecs.imread(file);
      // Creating an empty matrix to store the result
      Mat dst = new Mat();
      // Applying color map to an image
      Imgproc.applyColorMap(src, dst, Imgproc. COLORMAP_PINK);
      // Writing the image
      Imgcodecs.imwrite("D:\images\color_map.jpg", dst);
      System.out.println("Image processed");
   }
}

Input Image

Output

On executing, the above program generates the following output −