java:resize_image_with_imageio_and_graphics2d [Tutorial Site]

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====== Resize Image with ImageIO and Graphics2D ======
Here is how we do it. Note that the try catch exception is omitted here, you need to do it yourself.

  - Read the image file from storage as ''InputStream''
  - Read it as ''BufferedImage''
  - Create a new ''BufferedImage'' with new image width, height, and type. Here we assume we scale down 50% of each size of the image.
  - Create a ''Graphics2D'' object from the new BufferedImage.
  - Use the method ''Graphics2D.drawImage(...)'' to draw the input buffered image to the new buffered image
  - dispose the Graphics2D object.
  - Save the buffered image to file.

<code>
    imageInputStream = new FileInputStream("input.jpg");
    BufferedImage inputBufferedImage = ImageIO.read(imageInputStream);
    
    int scaledWidth = (int) (inputBufferedImage.getWidth() * 0.5f);
    int scaledHeight = (int) (inputBufferedImage.getHeight() * 0.5f);
    BufferedImage outputBufferedImage = new BufferedImage(scaledWidth, scaledHeight, memberImage.getType());
    
    Graphics2D g2d = outputBufferedImage.createGraphics();
    g2d.drawImage(inputBufferedImage, 0, 0, scaledWidth, scaledHeight, null);
    g2d.dispose();
    
    File outputFile = new File("output.jpg");
    ImageIO.write(outputBufferedImage, "jpg", outputFile);
</code>