摘要：
voidcreateThumbnail（Stringfilename，intthumbWidth，intthumHeight，intquality，StringoutFilename）throwsInterruptedException，FileNotFoundException，IOException｛//loadimagefromfilenameImageimage=Toolkit.getD
voidcreateThumbnail(String filename, intthumbWidth, intthumbHeight, intquality, String outFilename) throwsInterruptedException, FileNotFoundException, IOException { // load image from filename Image image = Toolkit.getDefaultToolkit().getImage(filename); MediaTracker mediaTracker = newMediaTracker(newContainer()); mediaTracker.addImage(image, 0); mediaTracker.waitForID(0); // use this to test for errors at this point: // System.out.println(mediaTracker.isErrorAny()); // determine thumbnail size from WIDTH and HEIGHT doublethumbRatio = (double)thumbWidth / (double)thumbHeight; intimageWidth = image.getWidth(null); intimageHeight = image.getHeight(null); doubleimageRatio = (double)imageWidth / (double)imageHeight; if(thumbRatio < imageRatio) { thumbHeight = (int)(thumbWidth / imageRatio); } else{ thumbWidth = (int)(thumbHeight * imageRatio); } // draw original image to thumbnail image object and // scale it to the new size on-the-fly BufferedImage thumbImage = newBufferedImage(thumbWidth, thumbHeight, BufferedImage.TYPE_INT_RGB); Graphics2D graphics2D = thumbImage.createGraphics(); graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR); graphics2D.drawImage(image, 0, 0, thumbWidth, thumbHeight, null); // save thumbnail image to outFilename BufferedOutputStream out = newBufferedOutputStream(newFileOutputStream(outFilename)); JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out); JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(thumbImage); quality = Math.max(0, Math.min(quality, 100)); param.setQuality((float)quality / 100.0f, false); encoder.setJPEGEncodeParam(param); encoder.encode(thumbImage); out.close(); }