How to 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 −