package bugs.jpeg;

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

/**
 * This test program demonstrates a critical bug in the
 * JPEG writer of ImageIO. When a BufferedImage is written
 * to a JPEG file all colors are garbled if the BufferdImage
 * contains an alpha channel. As JPEG does not support
 * an alpha channel the writer should just ignore it
 * but otherwise leave the colors intact.
 * 
 * This bug is especially critical for JavaFX users because
 * all JavaFX images converted to BufferedImages do contain
 * an alpha channel and converting to a BufferdImage and writing
 * in out via ImageIO is the only way to write an image in JavaFX.
 * 
 * This was also reported as:
 * http://javafx-jira.kenai.com/browse/RT-23502
 * 
 * @author M. Paus
 */
public class ImageIOJpegBug {
	
	static final String IMG_FORMAT = "jpeg";
	
	static final int[] IMG_TYPES = new int[]{
		BufferedImage.TYPE_INT_RGB,			// 1 - ok
		BufferedImage.TYPE_INT_ARGB,		// 2 - wrong
		BufferedImage.TYPE_INT_ARGB_PRE,	// 3 - wrong
		BufferedImage.TYPE_INT_BGR,			// 4 - ok
		BufferedImage.TYPE_3BYTE_BGR,		// 5 - ok
		BufferedImage.TYPE_4BYTE_ABGR,		// 6 - wrong
		BufferedImage.TYPE_4BYTE_ABGR_PRE,	// 7 - wrong
		BufferedImage.TYPE_USHORT_565_RGB,	// 8 - ok
		BufferedImage.TYPE_USHORT_555_RGB,	// 9 - ok
	};

	public static void main(String[] args) {
		for (int imgType : IMG_TYPES) {
			BufferedImage bi = new BufferedImage(600, 400, imgType);
			Graphics2D g2 = (Graphics2D)bi.getGraphics();
			g2.setColor(Color.WHITE);
			g2.fillRect(0, 0, bi.getWidth(), bi.getHeight());
			g2.setColor(Color.RED);
			g2.drawString("RED", 100, 100);
			g2.setColor(Color.GREEN);
			g2.drawString("GREEN", 200, 200);
			g2.setColor(Color.BLUE);
			g2.drawString("BLUE", 300, 300);
			try {
				String filename = "image_type" + imgType + "." + IMG_FORMAT;
				ImageIO.write(bi, IMG_FORMAT, new File(filename));
				System.out.println(filename + " written.");
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}

}