PPTX to PNG color rendering – Apache POI

Question

I am converting pptx slides to png by using POI library but it does not render correctly the slide’s colors, for example, instead of rendering turquoise it will render gray. I tried to convert pptx slides to svg but got the same problem, so I was wondering if it has something to do with XMLSlideShow class or XSLFSlide class. Any help will be greatly appreciated!

Code:

String file = "C:\\Users\\ABC\\demo1.pptx";
XMLSlideShow ppt = null;

ppt = new XMLSlideShow(OPCPackage.open(new File(file)));    
Dimension pgsize = ppt.getPageSize();
float scale = 1;
int width = (int) (pgsize.width * scale);
int height = (int) (pgsize.height * scale);

XSLFSlide[] slide = ppt.getSlides();

for (int i = 0; i < slide.length; i++) {
    String title = slide[i].getTitle();

    BufferedImage img = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    Graphics2D graphics = img.createGraphics();

    graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
    graphics.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
    graphics.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC);
    graphics.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON);
    graphics.setColor(Color.white);
    graphics.clearRect(0, 0, width, height);
    graphics.scale(scale, scale);

    slide[i].draw(graphics);

    int sep = file.lastIndexOf(".");
    String fname = file.substring(0, sep == -1 ? file.length() : sep) + "-" + (i + 1) +".png";

    FileOutputStream out = new FileOutputStream(fname);
    ImageIO.write(img, "png", out);
    out.close();
}   

Answer 1

This is a problem with apache POI library. Please use a older version i.e. 3.7 that might solve your problem.