Java Utililty Methods BufferedImage to Transparent

if (i == null)
    return null;
final int t = i.getRGB(0, i.getHeight() - 1) & 0x00FFFFFF;
ImageFilter filter = new RGBImageFilter() {
    @Override
    public int filterRGB(int x, int y, int rgb) {
        if ((rgb & 0x00FFFFFF) == t)
            return t;
...

int i = origImage.getWidth();
int j = origImage.getHeight();
BufferedImage compTransImg = new BufferedImage(i, j, BufferedImage.TYPE_INT_ARGB);
for (int k = 0; k < j; k++) {
    for (int m = 0; m < i; m++) {
        int color = origImage.getRGB(m, k);
        int compColor = compImg.getRGB(m, k);
        int alpha = (color >> 24) & 0xff;
...

RGBImageFilter filter = new RGBImageFilter() {
    public int markerRGB = color.getRGB() | 0xFF000000;
    public final int filterRGB(int x, int y, int rgb) {
        if ((rgb | 0xFF000000) == markerRGB) {
            return 0x00FFFFFF & rgb;
        } else {
            return rgb;
};
ImageProducer ip = new FilteredImageSource(im.getSource(), filter);
Image image = Toolkit.getDefaultToolkit().createImage(ip);
BufferedImage bufferedImage = new BufferedImage(image.getWidth(null), image.getHeight(null),
        BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = bufferedImage.createGraphics();
g2.drawImage(image, 0, 0, null);
g2.dispose();
return bufferedImage;

ImageFilter filter = new RGBImageFilter() {
    public int markerRGB = color.getRGB() | 0xFF000000;
    public final int filterRGB(int x, int y, int rgb) {
        if ((rgb | 0xFF000000) == markerRGB) {
            return 0x00FFFFFF & rgb;
        } else {
            return rgb;
};
ImageProducer ip = new FilteredImageSource(im.getSource(), filter);
return Toolkit.getDefaultToolkit().createImage(ip);

BufferedImage dimg = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g = dimg.createGraphics();
g.setComposite(AlphaComposite.Src);
g.drawImage(image, null, 0, 0);
g.dispose();
for (int i = 0; i < dimg.getHeight(); i++) {
    for (int j = 0; j < dimg.getWidth(); j++) {
        if (dimg.getRGB(j, i) == color.getRGB()) {
...

final ImageFilter filter = new RGBImageFilter() {
    public int markerRGB = color.getRGB() | 0xFF000000;
    @Override
    public final int filterRGB(final int x, final int y, final int rgb) {
        if ((rgb | 0xFF000000) == markerRGB) {
            return 0x00FFFFFF & rgb;
        return rgb;
...

final ImageFilter transparencyfilter = new RGBImageFilter() {
    @Override
    public int filterRGB(int x, int y, int rgb) {
        final Color filterColor = new Color(rgb);
        if (colorsAreSimilar(filterColor, colorToMakeTransparent, tolerance)) {
            return 0x00FFFFFF & rgb;
        } else {
            return rgb;
...

ImageFilter filter = new RGBImageFilter() {
    public int markerRGB = color.getRGB() | 0xFF000000;
    public final int filterRGB(int x, int y, int rgb) {
        if ((rgb | 0xFF000000) == markerRGB) {
            return 0x00FFFFFF & rgb;
        } else {
            return rgb;
};
ImageProducer ip = new FilteredImageSource(im.getSource(), filter);
return Toolkit.getDefaultToolkit().createImage(ip);

Makes the given color in the given Image transparent.

ImageFilter filter = new RGBImageFilter() {
    @Override
    public final int filterRGB(int x, int y, int rgb) {
        if (rgb == transparentColor.getRGB()) {
            return rgb & 0xFFFFFF; 
        return rgb;
};
ImageProducer ip = new FilteredImageSource(image.getSource(), filter);
return Toolkit.getDefaultToolkit().createImage(ip);

BufferedImage bi = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TRANSLUCENT);
Graphics2D g = bi.createGraphics();
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, transparency));
g.drawImage(image, null, 0, 0);
g.dispose();
return bi;