public static void makeThumbnails() throws IOException { File in = new File("D:/public_html/poke/screenshots"); File out = new File(in.getParent(), "thumbs/"); out.mkdir(); for (File f : in.listFiles()) { String name = f.getName(); if (name.endsWith(".png")) { BufferedImage src = ImageIO.read(f), thumb = new BufferedImage(50, 50, BufferedImage.TYPE_INT_RGB); Graphics g = thumb.getGraphics(); g.drawImage(src, 0, 0, 50, 50, null); g.dispose(); ImageIO.write(thumb, "png", new File(out, name)); } } }