BufferedImageUtils.java 文件源码

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();
}