ImageUtils.java

package org.herac.tuxguitar.gui.util;

import java.io.ByteArrayOutputStream;
import java.io.OutputStream;

import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.ImageLoader;
import org.eclipse.swt.graphics.PaletteData;
import org.eclipse.swt.graphics.RGB;

public class ImageUtils {
  /**
   * Crea una mascara a partir de src.
   * 
   * @param src
   * @param alpha
   * @param none
   * @return ImageData
   */
  public static ImageData applyMask(ImageData src, RGB alpha, RGB none) {
    ImageData maskData = new ImageData(src.width, src.height, 1,
        new PaletteData(new RGB[] { none, alpha }));
    for (int x = 0; x < maskData.width; x++) {
      for (int y = 0; y < maskData.height; y++) {
        RGB rgb = src.palette.getRGB(src.getPixel(x, y));
        if (rgb.red == alpha.red && rgb.green == alpha.green
            && rgb.blue == alpha.blue) {
          maskData.setPixel(x, y, maskData.palette.getPixel(none));
        } else {
          maskData.setPixel(x, y, maskData.palette.getPixel(alpha));
        }
      }
    }
    return maskData;
  }

  /**
   * Convierte un ImageData en un array de bytes
   * 
   * @param data
   * @param format
   * @return
   */
  public static byte[] imageToByteArray(ImageData data, int format) {
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    writeImage(data, out, format);
    return out.toByteArray();
  }

  /**
   * Escribe el ImageData en el outputStream
   * 
   * @param data
   * @param outputStream
   * @param format
   */
  public static void writeImage(ImageData data, OutputStream outputStream,
      int format) {
    ImageLoader loader = new ImageLoader();
    loader.data = new ImageData[] { data };
    loader.save(outputStream, format);
  }
}