PDF to PNG conversion problem

Hi Aspose,
I am trying to convert a pdf document to a png image, in order to present it in a previewer.
However, conversionwill neverend.

Here is what I do:
com.aspose.pdf.Document pdfDocument = new com.aspose.pdf.Document(srcFile.getAbsolutePath());
FileOutputStream out = new FileOutputStream(filePage);
com.aspose.pdf.devices.Resolution resolution = new com.aspose.pdf.devices.Resolution(200);
com.aspose.pdf.devices.PngDevice pngDevice = new com.aspose.pdf.devices.PngDevice(resolution);
            pngDevice.process(pdfDocument.getPages().get_Item(pageNum), out);

Test file in attachment.

How to fix it?
Thanks,
Piotr