Image Processing in Java – Creating a Random Pixel Image

Prerequisites:

• Image Processing in Java – Read and Write
• Image Processing In Java – Get and Set Pixels
• Image Processing in Java – Colored Image to Grayscale Image Conversion
• Image Processing in Java – Colored Image to Negative Image Conversion
• Image Processing in Java – Colored to Red Green Blue Image Conversion
• Image Processing in Java – Colored Image to Sepia Image Conversion

In this article, we will be creating a random pixel image. For creating a random pixel image, we don’t need any input image. We can create an image file and set its pixel values generated randomly.

A random image is an image in which the pixels are chosen at random, so they can take any color from the desired palette (generally 16 million colors). The resulting images look like multi-colored noise backgrounds.

Algorithm:

1. Set the dimension of the new image file.
2. Create a BufferedImage object to hold the image. This object is used to store an image in RAM.
3. Generate random number values for alpha, red, green, and blue components.
4. Set the randomly generated ARGB (Alpha, Red, Green, and Blue) values.
5. Repeat steps 3 and 4 for each pixel of the image.

Implementation:

Java

// Java program to demonstrate
// creation of random pixel image

import java.io.File;
import java.io.IOException;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;

public class RandomImage
{
    public static void main(String args[])throws IOException
    {
        // Image file dimensions
        int width = 640, height = 320;

        // Create buffered image object
        BufferedImage img = null;
        img = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);

        // file object
        File f = null;

        // create random values pixel by pixel
        for (int y = 0; y < height; y++)
        {
            for (int x = 0; x < width; x++)
            {
                  // generating values less than 256
                int a = (int)(Math.random()*256);
                int r = (int)(Math.random()*256);
                int g = (int)(Math.random()*256);
                int b = (int)(Math.random()*256);

                  //pixel
                int p = (a<<24) | (r<<16) | (g<<8) | b;

                img.setRGB(x, y, p);
            }
        }

        // write image
        try
        {
            f = new File("C:/Users/hp/Desktop/Image Processing in Java/gfg-logo.png");
            ImageIO.write(img, "png", f);
        }
        catch(IOException e)
        {
            System.out.println("Error: " + e);
        }
    }
}

Output:

Note: Code will not run on online ide since it writes image in drive.