PixelImage.java

import java.awt.image.BufferedImage;
import java.awt.image.Raster;
import java.awt.image.WritableRaster;

/**
 * Provides an interface to a picture as an array of Pixels
 * 
 * @author Richard Dunn, Tim Gesell, modified by Pranav Kadekodi
 * @version November 5th 2023
 */
public class PixelImage
{
    private BufferedImage myImage;
    private int width;
    private int height;

    /**
     * Map this PixelImage to a real image
     * @param bi The image
     */
    public PixelImage(BufferedImage bi)
    {
        // initialise instance variables
        this.myImage = bi;
        this.width = bi.getWidth();
        this.height = bi.getHeight();
    }

    /**
     * accessor for width instance variable
     */
    public int getWidth() {
        return this.width;
    }

    /**
     * accessor for height instance value
     */
    public int getHeight() {
        return this.height;
    }

    /**
     * accessor for myImage instance value
     */
    public BufferedImage getImage() {
        return this.myImage;
    }

    /**
     * Return the image's pixel data as an array of Pixels.  The
     * first coordinate is the x-coordinate, so the size of the 
     * array is [width][height], where width and height are the 
     * dimensions of the array
     * @return The array of pixels
     */
    public Pixel[][] getData() {
        Raster r = this.myImage.getRaster();
        Pixel[][] data = new Pixel[r.getHeight()][r.getWidth()];
        int[] colorLevels = new int[3];

        for (int row = 0; row < r.getHeight(); row++) {
            for (int col = 0; col < r.getWidth(); col++) {
                colorLevels = r.getPixel(col, row, colorLevels);
                Pixel newPixel = new Pixel(colorLevels[0], colorLevels[1], colorLevels[2]);
                data[row][col] = newPixel;
            }
        }

        return data;
    }

    /**
     * Set the image's pixel data from an array.  This array matches
     * that returned by getData().  It is an error to pass in an
     * array that does not match the image's dimensions or that
     * has pixels with invalid values (not 0-255)
     * @param data The array to pull from
     */
    public void setData(Pixel[][] data) throws IllegalArgumentException {
        int[] pixelValues = new int[3];     // a temporary array to hold r,g,b values
        WritableRaster wr = this.myImage.getRaster();

        if (data.length != wr.getHeight()) {
            throw new IllegalArgumentException("Array size does not match");
        } else if (data[0].length != wr.getWidth()) {
            throw new IllegalArgumentException("Array size does not match");
        }

        for (int row = 0; row < wr.getHeight(); row++) {
            for (int col = 0; col < wr.getWidth(); col++) {
                pixelValues[0] = data[row][col].getRed();
                pixelValues[1] = data[row][col].getGreen();
                pixelValues[2] = data[row][col].getBlue();
                wr.setPixel(col, row, pixelValues);
            }
        }
    }
}