ImageOperations.java 文件源码

/**
 * The next two mehtds where got from http://javaalmanac
 * .com/egs/java.awt.image/HasAlpha.html T
 * 
 * @param image
 * @return
 */
// This method returns true if the specified
// image has transparent pixels
public static boolean hasAlpha(Image image) {
    // If buffered image, the color model is
    // readily available
    if (image instanceof BufferedImage) {
        BufferedImage bimage = (BufferedImage) image;
        return bimage.getColorModel().hasAlpha();
    }

    // Use a pixel grabber to retrieve the
    // image's color model;
    // grabbing a single pixel is usually
    // sufficient
    PixelGrabber pg = new PixelGrabber(image, 0, 0, 1, 1, false);
    try {
        pg.grabPixels();
    } catch (InterruptedException e) {
    }

    // Get the image's color model
    ColorModel cm = pg.getColorModel();
    return cm.hasAlpha();
}