A Java small class to invert colors in image files. The library edu.duke is a dependency for the class to work, it should be added into the Java IDE to compile with no errors. Download link http://www.dukelearntoprogram.com/downloads/archives/courserajava.jar

BatchInversions.java

/**
 * Inverts colors in a image file (photographic negative).
 * 
 * @author (Elvis Morales) 
 * @version (1.0)
 */

import edu.duke.*;
import java.io.File;

public class BatchInversions {
    
    public ImageResource makeInversion(ImageResource inImage) {
        
        ImageResource outImage = new ImageResource(inImage);
        
        for (Pixel pixel: outImage.pixels()) {
            
            Pixel inPixel = inImage.getPixel(pixel.getX(), pixel.getY());
            
            int invRed = 255 - inPixel.getRed();
            int invGreen = 255 - inPixel.getGreen();
            int invBlue = 255 - inPixel.getBlue();
            
            pixel.setRed(invRed);
            
            pixel.setGreen(invGreen);
           
            pixel.setBlue(invBlue);
        }
        
        return outImage;
        
    }
    
    public void selectAndConvert() {
        DirectoryResource dr = new DirectoryResource();
        for (File f : dr.selectedFiles()) {
            ImageResource inImage = new ImageResource(f);
            ImageResource imageInv = makeInversion(inImage);
            imageInv.setFileName("inverted-" + inImage.getFileName());
            imageInv.draw();
            imageInv.save();
        }
    }
    
}