Java 将 Image 转换为 BufferedImage

Question

已经有这样的问题 link在 StackOverflow 上，接受的答案是“casting”:

Image image = ImageIO.read(new File(file));
BufferedImage buffered = (BufferedImage) image;

在我的程序中我尝试:

final float FACTOR  = 4f;
BufferedImage img = ImageIO.read(new File("graphic.png"));
int scaleX = (int) (img.getWidth() * FACTOR);
int scaleY = (int) (img.getHeight() * FACTOR);
Image image = img.getScaledInstance(scaleX, scaleY, Image.SCALE_SMOOTH);
BufferedImage buffered = (BufferedImage) image;

不幸的是我得到了运行时错误:

sun.awt.image.ToolkitImage cannot be cast to java.awt.image.BufferedImage

显然转换不起作用。
问题是:将 Image 转换为 BufferedImage 的正确方法是什么(或是否存在)？

Answer 1

来自 Java Game Engine :

/**
 * Converts a given Image into a BufferedImage
 *
 * @param img The Image to be converted
 * @return The converted BufferedImage
 */
public static BufferedImage toBufferedImage(Image img)
{
    if (img instanceof BufferedImage)
    {
        return (BufferedImage) img;
    }

    // Create a buffered image with transparency
    BufferedImage bimage = new BufferedImage(img.getWidth(null), img.getHeight(null), BufferedImage.TYPE_INT_ARGB);

    // Draw the image on to the buffered image
    Graphics2D bGr = bimage.createGraphics();
    bGr.drawImage(img, 0, 0, null);
    bGr.dispose();

    // Return the buffered image
    return bimage;
}