更快的高质量图像缩放getFasterScaledInstance，来自Filthy Rich Clients

public static BufferedImage getFasterScaledInstance(BufferedImage img, int targetWidth, int targetHeight, Object hint, boolean progressiveBilinear) { int type = (img.getTransparency() == Transparency.OPAQUE) ? BufferedImage.TYPE_INT_RGB : BufferedImage.TYPE_INT_ARGB; BufferedImage ret = img; BufferedImage scratchImage = null; Graphics2D g2 = null; int w, h; int prevW = ret.getWidth(); int prevH = ret.getHeight(); boolean isTranslucent = img.getTransparency() != Transparency.OPAQUE; if (progressiveBilinear) { // Use multi-step technique: start with original size, then // scale down in multiple passes with drawImage() // until the target size is reached w = img.getWidth(); h = img.getHeight(); w = w < targetWidth || h < targetHeight ? targetWidth : w; h = w < targetWidth || h < targetHeight ? targetHeight : h; } else { // Use one-step technique: scale directly from original // size to target size with a single drawImage() call w = targetWidth; h = targetHeight; } do { if (progressiveBilinear && w > targetWidth) { w /= 2; if (w < targetWidth) { w = targetWidth; } } if (progressiveBilinear && h > targetHeight) { h /= 2; if (h < targetHeight) { h = targetHeight; } } if (scratchImage == null || isTranslucent) { // Use a single scratch buffer for all iterations // and then copy to the final, correctly-sized image // before returning scratchImage = new BufferedImage(w, h, type); g2 = scratchImage.createGraphics(); } RenderingHints rh = new RenderingHints( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); rh.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY); rh.put(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON); rh.put(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON); rh.put(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); rh.put(RenderingHints.KEY_INTERPOLATION, hint); g2.setRenderingHints(rh); g2.drawImage(ret, 0, 0, w, h, 0, 0, prevW, prevH, null); prevW = w; prevH = h; ret = scratchImage; } while (w != targetWidth || h != targetHeight); if (g2 != null) { g2.dispose(); } // If we used a scratch buffer that is larger than our target size, // create an image of the right size and copy the results into it if (targetWidth != ret.getWidth() || targetHeight != ret.getHeight()) { scratchImage = new BufferedImage(targetWidth, targetHeight, type); g2 = scratchImage.createGraphics(); g2.drawImage(ret, 0, 0, null); g2.dispose(); ret = scratchImage; } return ret; }