画像に (Java を使用して) 影の効果を作成しようとしています。
関連する複数の質問を見て、提案された解決策のいくつかを実装しました。残念ながら、私は常に同じ問題を抱えています。影の効果により、画像全体が灰色 (つまり、影の色) に再描画されるため、元の画像が表示されなくなります。
私がテストしたコードの例 (JIDE の自由に利用できるライブラリに基づく):
ShadowFactory sf = new ShadowFactory(2, 0.5f, Color.black);
ImageIO.write(sf.createShadow(ImageIO.read(new File("c:\\out2.png"))), "png", new File("c:\\out3.png"));
これを複数のソース ファイル (out2.png) でテストしたことは言うまでもありません。
私は無知です：ヒント/ヘルプは大歓迎です。
全体的な理論は単純です。基本的に、画像のマスクを生成する必要があります ( を使用し、AlphaCompositeその結果の画像を必要な色で塗りつぶします (また を使用しAlphaCompositeます。もちろん、これはすべて画像のアルファ チャネルで機能します...
そのマスクを取得したら、2 つの画像を結合する必要があります (元の画像をマスクされた画像に重ねます)。
この例では、JHLabs フィルターを使用してぼかしを提供しています...
public class TestImageDropShadow {
public static void main(String[] args) {
new TestImageDropShadow();
}
public TestImageDropShadow() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new ImagePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class ImagePane extends JPanel {
private BufferedImage background;
public ImagePane() {
try {
BufferedImage master = ImageIO.read(getClass().getResource("/Scaled.png"));
background = applyShadow(master, 5, Color.BLACK, 0.5f);
} catch (IOException ex) {
Logger.getLogger(TestImageDropShadow.class.getName()).log(Level.SEVERE, null, ex);
}
}
@Override
public Dimension getPreferredSize() {
return background == null ? super.getPreferredSize() : new Dimension(background.getWidth(), background.getHeight());
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (background != null) {
int x = (getWidth() - background.getWidth()) / 2;
int y = (getHeight() - background.getHeight()) / 2;
g.drawImage(background, x, y, this);
}
}
}
public static void applyQualityRenderingHints(Graphics2D g2d) {
g2d.setRenderingHint(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setRenderingHint(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_DITHERING, RenderingHints.VALUE_DITHER_ENABLE);
g2d.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON);
g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2d.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_PURE);
}
public static BufferedImage createCompatibleImage(int width, int height) {
return createCompatibleImage(width, height, Transparency.TRANSLUCENT);
}
public static BufferedImage createCompatibleImage(int width, int height, int transparency) {
BufferedImage image = getGraphicsConfiguration().createCompatibleImage(width, height, transparency);
image.coerceData(true);
return image;
}
public static BufferedImage createCompatibleImage(BufferedImage image) {
return createCompatibleImage(image, image.getWidth(), image.getHeight());
}
public static BufferedImage createCompatibleImage(BufferedImage image,
int width, int height) {
return getGraphicsConfiguration().createCompatibleImage(width, height, image.getTransparency());
}
public static GraphicsConfiguration getGraphicsConfiguration() {
return GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice().getDefaultConfiguration();
}
public static BufferedImage generateMask(BufferedImage imgSource, Color color, float alpha) {
int imgWidth = imgSource.getWidth();
int imgHeight = imgSource.getHeight();
BufferedImage imgBlur = createCompatibleImage(imgWidth, imgHeight);
Graphics2D g2 = imgBlur.createGraphics();
applyQualityRenderingHints(g2);
g2.drawImage(imgSource, 0, 0, null);
g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_IN, alpha));
g2.setColor(color);
g2.fillRect(0, 0, imgSource.getWidth(), imgSource.getHeight());
g2.dispose();
return imgBlur;
}
public static BufferedImage generateBlur(BufferedImage imgSource, int size, Color color, float alpha) {
GaussianFilter filter = new GaussianFilter(size);
int imgWidth = imgSource.getWidth();
int imgHeight = imgSource.getHeight();
BufferedImage imgBlur = createCompatibleImage(imgWidth, imgHeight);
Graphics2D g2 = imgBlur.createGraphics();
applyQualityRenderingHints(g2);
g2.drawImage(imgSource, 0, 0, null);
g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_IN, alpha));
g2.setColor(color);
g2.fillRect(0, 0, imgSource.getWidth(), imgSource.getHeight());
g2.dispose();
imgBlur = filter.filter(imgBlur, null);
return imgBlur;
}
public static BufferedImage applyShadow(BufferedImage imgSource, int size, Color color, float alpha) {
BufferedImage result = createCompatibleImage(imgSource, imgSource.getWidth() + (size * 2), imgSource.getHeight() + (size * 2));
Graphics2D g2d = result.createGraphics();
g2d.drawImage(generateShadow(imgSource, size, color, alpha), size, size, null);
g2d.drawImage(imgSource, 0, 0, null);
g2d.dispose();
return result;
}
public static BufferedImage generateShadow(BufferedImage imgSource, int size, Color color, float alpha) {
int imgWidth = imgSource.getWidth() + (size * 2);
int imgHeight = imgSource.getHeight() + (size * 2);
BufferedImage imgMask = createCompatibleImage(imgWidth, imgHeight);
Graphics2D g2 = imgMask.createGraphics();
applyQualityRenderingHints(g2);
int x = Math.round((imgWidth - imgSource.getWidth()) / 2f);
int y = Math.round((imgHeight - imgSource.getHeight()) / 2f);
g2.drawImage(imgSource, x, y, null);
g2.dispose();
// ---- Blur here ---
BufferedImage imgGlow = generateBlur(imgMask, (size * 2), color, alpha);
return imgGlow;
}
public static Image applyMask(BufferedImage sourceImage, BufferedImage maskImage) {
return applyMask(sourceImage, maskImage, AlphaComposite.DST_IN);
}
public static BufferedImage applyMask(BufferedImage sourceImage, BufferedImage maskImage, int method) {
BufferedImage maskedImage = null;
if (sourceImage != null) {
int width = maskImage.getWidth(null);
int height = maskImage.getHeight(null);
maskedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
Graphics2D mg = maskedImage.createGraphics();
int x = (width - sourceImage.getWidth(null)) / 2;
int y = (height - sourceImage.getHeight(null)) / 2;
mg.drawImage(sourceImage, x, y, null);
mg.setComposite(AlphaComposite.getInstance(method));
mg.drawImage(maskImage, 0, 0, null);
mg.dispose();
}
return maskedImage;
}
}
これは私のバージョンです:
private static Image dropShadow(BufferedImage img) {
// a filter which converts all colors except 0 to black
ImageProducer prod = new FilteredImageSource(img.getSource(), new RGBImageFilter() {
@Override
public int filterRGB(int x, int y, int rgb) {
if (rgb == 0)
return 0;
else
return 0xff000000;
}
});
// create whe black image
Image shadow = Toolkit.getDefaultToolkit().createImage(prod);
// result
BufferedImage result = new BufferedImage(img.getWidth(), img.getHeight(), img.getType());
Graphics2D g = (Graphics2D) result.getGraphics();
// draw shadow with offset
g.drawImage(shadow, 10, 0, null);
// draw original image
g.drawImage(img, 0, 0, null);
return result;
}