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Draw transparency of image on BufferStrategy

Good day,
I tried to draw a picture on a BufferStrategy with its Graphics. The picture has a transparent background and if I draw it on the screen the transparent areas change to black.
The blue thing is the image I want to draw but without the black parts (in the original picture they are not there).
That is how I draw the picture:
BufferedImage image = loadImage(path);
g.drawImage(image, x, y, null);
public BufferedImage loadImage(String path) {
ImageIcon icon = new ImageIcon(this.getClass().getClassLoader().getResource(path));
BufferedImage image = new BufferedImage(icon.getIconWidth(), icon.getIconHeight(), BufferedImage.TYPE_INT_RGB);
Graphics g = image.createGraphics();
icon.paintIcon(null, g, 0, 0);
g.dispose();
return image;
}

The comment from Andreas is correct but is should be ARGB rather than RGBA.
To do this just change BufferedImage.TYPE_INT_RGB in this line:
BufferedImage image = new BufferedImage(icon.getIconWidth(), icon.getIconHeight(), BufferedImage.TYPE_INT_RGB);
To BufferedImage.TYPE_INT_ARGB:
BufferedImage image = new BufferedImage(icon.getIconWidth(), icon.getIconHeight(), BufferedImage.TYPE_INT_ARGB);
Edit in response to your comment, here is the complete answer:
In addition to creating a BufferedImage as TYPE_INT_ARGB you also need to apply the AlphaComposite SRC_OVER to your buffered image using Graphics2D like this:
public static BufferedImage loadImage(String path)
{
ImageIcon icon = new ImageIcon(path);
//using TYPE_INT_ARGB
BufferedImage image = new BufferedImage(icon.getIconWidth(), icon.getIconHeight(), BufferedImage.TYPE_INT_ARGB);
//changed to G2D change here
Graphics2D g2d = image.createGraphics();
//get alpha
AlphaComposite ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER);
//set alpha
g2d.setComposite(ac);
icon.paintIcon(null, g2d, 0, 0);
g2d.dispose();
return image;
}

How to convert an image to greyscale?

I want to simply convert an image to greyscale. But all I get is a completely black image. Why?
BufferedImage original = ImageIO.read(url);
BufferedImage image = new BufferedImage(original.getWidth(), original.getHeight(), BufferedImage.TYPE_BYTE_GRAY);
Graphics g = image.getGraphics();
g.drawImage(image, 0, 0, null);
g.dispose();
It has the correct width and height like the source image, but is completely black...

You are writing empty image to itself.
Change
g.drawImage(image, 0, 0, null);
to
g.drawImage(original, 0, 0, null);

Java rescaling an image creating half white half grey image

I am having a problem with the Grapics2D API, I am trying to re-size an image but instead of getting the smaller image its showing a half white and half grey area. what am I doing wrong? I tried with and without render hints and it didn't work, or is there another approach that will give me a new Buffered Image object at the specified size?
//height = 400, width = 600, capture_rect = screen size
BufferedImage img = robot.createScreenCapture(CAPTURE_RECT);
BufferedImage resized = new BufferedImage(WIDTH, HEIGHT, img.getType());
Graphics2D g = resized.createGraphics();
g.drawImage(img, 0, 0, WIDTH, HEIGHT, 0, 0, img.getWidth(), img.getHeight(), null);
g.dispose();
setImage(resized);

See the article on Perils of Image.getScaledImage. It has some recommendations.
Here is some code it recommends:
private float xScaleFactor, yScaleFactor = ...;
private BufferedImage originalImage = ...;
public void paintComponent(Graphics g) {
Graphics2D g2 = (Graphics2D)g;
int newW = (int)(originalImage.getWidth() * xScaleFactor);
int newH = (int)(originalImage.getHeight() * yScaleFactor);
g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2.drawImage(originalImage, 0, 0, newW, newH, null);
}
It looks like you just need to specify the new width/height and it will do the scaling for you automatically.
Or maybe the problem is with the img.getType() method. You should be able to just using:
BufferedImage.TYPE_INT_RGB // (or ARGB)
See which works the best.

Resizing photos without text .. is RenderingHints necessary?

I am writing a quick little java class that resizes an image into various smaller sizes (thumbnail large/small/etc). I have seen examples that have RenderingHints in it. The output file is significantly larger than without.
My question is: Is it necessary to use RenderingHints if the images that are being resized have no text?
int IMG_WIDTH = 100;
int IMG_HEIGHT = 100;
BufferedImage resizedImage = new BufferedImage(IMG_WIDTH, IMG_HEIGHT, type);
Graphics2D g = resizedImage.createGraphics();
g.drawImage(originalImage, 0, 0, IMG_WIDTH, IMG_HEIGHT, null);
g.dispose();
g.setComposite(AlphaComposite.Src);
g.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
I started with a 45kb image, and the output difference is a 3kb file (without RenderingHints) versus a 24kb file (with RenderingHints)

I suppose, after reading the following stackoverflow.com question/answer:
Java Text on Image
I am inclined to think that RenderingHints will provide no benefit for me when the photos contain no text ... In which case, no text = no RenderingHints = smaller resized image

Set BufferedImage to be a color in Java

I need to create a rectangular BufferedImage with a specified background color, draw some pattern on the background and save it to file. I don't know how to create the background.
I am using a nested loop:
BufferedImage b_img = ...
for every row
for every column
setRGB(r,g,b);
But it's very slow when the image is large.
How to set the color in a more efficient way?

Get the graphics object for the image, set the current paint to the desired colour, then call fillRect(0,0,width,height).
BufferedImage b_img = ...
Graphics2D graphics = b_img.createGraphics();
graphics.setPaint ( new Color ( r, g, b ) );
graphics.fillRect ( 0, 0, b_img.getWidth(), b_img.getHeight() );

Probably something like:
BufferedImage image = new BufferedImage(...);
Graphics2D g2d = image.createGraphics();
g2d.setColor(...);
g2d.fillRect(...);

Use this:
BufferedImage bi = new BufferedImage(width, height,
BufferedImage.TYPE_INT_ARGB);
Graphics2D ig2 = bi.createGraphics();
ig2.setBackground(Color.WHITE);
ig2.clearRect(0, 0, width, height);

BufferedImage image = new BufferedImage(width,height, BufferedImage.TYPE_INT_ARGB);
int[]data=((DataBufferInt) image.getRaster().getDataBuffer()).getData();
Arrays.fill(data,color.getRGB());

For who want also to save the created image to a file, I have used previous answers and added the file saving part:
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.color.ColorSpace;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
// Create the image
BufferedImage bi = new BufferedImage(80, 40, ColorSpace.TYPE_RGB);
Graphics2D graphics = bi.createGraphics();
// Fill the background with gray color
Color rgb = new Color(50, 50, 50);
graphics.setColor (rgb);
graphics.fillRect ( 0, 0, bi.getWidth(), bi.getHeight());
// Save the file in PNG format
File outFile = new File("output.png");
ImageIO.write(bi, "png", outFile);
You can also save the image in other formats like bmp, jpg, etc...