ImageUtils.java

package org.eclipse.swt.util;

import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.DirectColorModel;
import java.awt.image.IndexColorModel;
import java.awt.image.WritableRaster;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.PaletteData;
import org.eclipse.swt.graphics.RGB;

public class ImageUtils {

	private ImageUtils() {
	}

	/**
	 * Converts an AWT image representation (BufferedImage) to its SWT equivalent
	 * (ImageData).
	 */
	public static ImageData convertBufferedImageToImageData(BufferedImage bufferedImage) {
		if (bufferedImage.getColorModel() instanceof DirectColorModel) {
			DirectColorModel colorModel = (DirectColorModel)bufferedImage.getColorModel();
			PaletteData palette = new PaletteData(colorModel.getRedMask(), colorModel.getGreenMask(), colorModel.getBlueMask());
			ImageData data = new ImageData(bufferedImage.getWidth(), bufferedImage.getHeight(), colorModel.getPixelSize(), palette);
			for (int y = 0; y < data.height; y++) {
				for (int x = 0; x < data.width; x++) {
					int rgb = bufferedImage.getRGB(x, y);
					int pixel = palette.getPixel(new RGB((rgb >> 16) & 0xFF, (rgb >> 8) & 0xFF, rgb & 0xFF));
					data.setPixel(x, y, pixel);
					if (colorModel.hasAlpha()) {
						data.setAlpha(x, y, (rgb >> 24) & 0xFF);
					}
				}
			}
			return data;
		} else if (bufferedImage.getColorModel() instanceof IndexColorModel) {
			IndexColorModel colorModel = (IndexColorModel)bufferedImage.getColorModel();
			int size = colorModel.getMapSize();
			byte[] reds = new byte[size];
			byte[] greens = new byte[size];
			byte[] blues = new byte[size];
			colorModel.getReds(reds);
			colorModel.getGreens(greens);
			colorModel.getBlues(blues);
			RGB[] rgbs = new RGB[size];
			for (int i = 0; i < rgbs.length; i++) {
				rgbs[i] = new RGB(reds[i] & 0xFF, greens[i] & 0xFF, blues[i] & 0xFF);
			}
			PaletteData palette = new PaletteData(rgbs);
			ImageData data = new ImageData(bufferedImage.getWidth(), bufferedImage.getHeight(), colorModel.getPixelSize(), palette);
			data.transparentPixel = colorModel.getTransparentPixel();
			WritableRaster raster = bufferedImage.getRaster();
			int[] pixelArray = new int[1];
			for (int y = 0; y < data.height; y++) {
				for (int x = 0; x < data.width; x++) {
					raster.getPixel(x, y, pixelArray);
					data.setPixel(x, y, pixelArray[0]);
				}
			}
			return data;
		} else {
			return null;
		}
	}

	/**
	 * Converts an SWT image representation (ImageData) to its AWT equivalent
	 * (BufferedImage).
	 */
	public static BufferedImage convertImageDataToBufferedImage(ImageData data) {
		ColorModel colorModel = null;
		PaletteData palette = data.palette;
		if (palette.isDirect) {
			colorModel = new DirectColorModel(data.depth, palette.redMask, palette.greenMask, palette.blueMask);
			BufferedImage bufferedImage = new BufferedImage(colorModel, colorModel.createCompatibleWritableRaster(data.width, data.height), false, null);
			for (int y = 0; y < data.height; y++) {
				for (int x = 0; x < data.width; x++) {
					int pixel = data.getPixel(x, y);
					RGB rgb = palette.getRGB(pixel);
					bufferedImage.setRGB(x, y, rgb.red << 16 | rgb.green << 8 | rgb.blue);
				}
			}
			return bufferedImage;
		} else {
			RGB[] rgbs = palette.getRGBs();
			byte[] red = new byte[rgbs.length];
			byte[] green = new byte[rgbs.length];
			byte[] blue = new byte[rgbs.length];
			for (int i = 0; i < rgbs.length; i++) {
				RGB rgb = rgbs[i];
				red[i] = (byte)rgb.red;
				green[i] = (byte)rgb.green;
				blue[i] = (byte)rgb.blue;
			}
			if (data.transparentPixel != -1) {
				colorModel = new IndexColorModel(data.depth, rgbs.length, red, green, blue, data.transparentPixel);
			} else {
				colorModel = new IndexColorModel(data.depth, rgbs.length, red, green, blue);
			}
			BufferedImage bufferedImage = new BufferedImage(colorModel, colorModel.createCompatibleWritableRaster(data.width, data.height), false, null);
			WritableRaster raster = bufferedImage.getRaster();
			int[] pixelArray = new int[1];
			for (int y = 0; y < data.height; y++) {
				for (int x = 0; x < data.width; x++) {
					int pixel = data.getPixel(x, y);
					pixelArray[0] = pixel;
					raster.setPixel(x, y, pixelArray);
				}
			}
			return bufferedImage;
		}
	}

}