Java konwertowanie obrazu do BufferedImage

Jest już takie pytanie link na StackOverflow i akceptowana odpowiedź to "casting":

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

W moim programie staram się:

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;

Niestety dostaję błąd run time:

Sun.awt.obraz.ToolkitImage nie może być wrzucany do Javy.awt.obraz.BufferedImage

Oczywiście casting nie działa.
Pytanie brzmi: jaki jest (lub jest) właściwy sposób konwersji obrazu na obraz BufferedImage?
Author: Community, 2012-11-28

4 answers

Z silnika gry Java :

/**
 * 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;
}
 85
Author: Sri Harsha Chilakapati,
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2015-05-28 04:50:28

Jednym ze sposobów radzenia sobie z tym jest utworzenie nowego obrazu BufferedImage i wskazanie, że obiekt graficzny rysuje skalowany obraz do nowego obrazu BufferedImage:

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 = new BufferedImage(scaleX, scaleY, TYPE);
buffered.getGraphics().drawImage(image, 0, 0 , null);
To powinno wystarczyć bez rzucania.
 18
Author: salbeira,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/doraprojects.net/template/agent.layouts/content.php on line 54
2012-11-28 12:51:08

Jeśli odzyskujesz sun.awt.image.ToolkitImage, możesz rzucić obraz do tego, a następnie użyć getBufferedImage () , aby uzyskać BufferedImage.

Więc zamiast ostatniej linijki kodu, w którym rzucasz, po prostu zrób:

BufferedImage buffered = ((ToolkitImage) image).getBufferedImage();
 2
Author: Hermann Hans,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/doraprojects.net/template/agent.layouts/content.php on line 54
2012-11-28 12:47:58

Jeśli używasz Kotlina, możesz dodać metodę rozszerzenia do obrazu w taki sam sposób, jak sugeruje Sri Harsha Chilakapati.

fun Image.toBufferedImage(): BufferedImage {
    if (this is BufferedImage) {
        return this
    }
    val bufferedImage = BufferedImage(this.getWidth(null), this.getHeight(null), BufferedImage.TYPE_INT_ARGB)

    val graphics2D = bufferedImage.createGraphics()
    graphics2D.drawImage(this, 0, 0, null)
    graphics2D.dispose()

    return bufferedImage
}

I użyj go tak:

myImage.toBufferedImage()
 2
Author: Steven Spungin,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/doraprojects.net/template/agent.layouts/content.php on line 54
2017-11-27 12:42:35