Lossless JPEG Rotate (90/180/270 degrees) in Java?

Question

Is there a Java library for rotating JPEG files in increments of 90 degrees, without incurring image degradation?

Answer 1

You don't need an external library for this kind of thing, it's all built into SE. The easiest being the rotate() function of the Graphics2D object.

For example:

   Image rotatedImage = new BufferedImage(imageToRotate.getHeight(null), imageToRotate.getWidth(null), BufferedImage.TYPE_INT_ARGB);

    Graphics2D g2d = (Graphics2D) rotatedImage.getGraphics();
    g2d.rotate(Math.toRadians(90.0));
    g2d.drawImage(imageToRotate, 0, -rotatedImage.getWidth(null), null);
    g2d.dispose();

no loss!

Or, if you want to be extra careful, just use BufferedImage.getRGB(x,y), and translate it pixel by pixel on to the new image.