Converting ppt to png using Apache poi

Hello I am trying to use the Apache Poi framework to convert each slide of a ppt to an individual png. The problem is that some slides are deformed. For instance there is a slide where the background has a rainbow color to it. And Images that are on some slides do not appear at all on the .png file

here is the code:

        FileInputStream is = new FileInputStream(args[0]);

        SlideShow ppt = new SlideShow(is);


        is.close();

        Dimension pgsize = ppt.getPageSize();

        Slide[] slide = ppt.getSlides();

        for (int i = 0; i < slide.length; i++) {

        BufferedImage img = new BufferedImage(pgsize.width, pgsize.height,
        BufferedImage.TYPE_INT_RGB);
        Graphics2D graphics = img.createGraphics();
        //cl开发者_C百科ear the drawing area
        graphics.setPaint(Color.white);
        graphics.fill(new Rectangle2D.Float(0, 0, pgsize.width, pgsize.height));

        //render
        slide[i].draw(graphics);

        //save the output
        FileOutputStream out = new FileOutputStream("C:\\Users\\Farzad\\Desktop\\slide-" + (i+1) + ".png");
        javax.imageio.ImageIO.write(img, "png", out);
        out.close();
        }

For this to work we don't have to use:

graphics.setPaint(Color.white);

Instead use :

graphics.setPaint(
    slideShow.getSlides()[0].getBackground().getFill().getForegroundColor()
);