String dataDir = Utils.getSharedDataDir(PNGToPDF.class) + "ConvertingImages/";
PngImage pngImage = (PngImage) Image.load(dataDir + "aspose_logo.png");
try
{
    PdfOptions exportOptions = new PdfOptions();
    exportOptions.setPdfDocumentInfo(new PdfDocumentInfo());

    pngImage.save("multipage_specificColor_.djvu4_ethalon.pdf", exportOptions);
}
finally
{
    pngImage.close();
}