我可以检测是否从多页PDF文件转换了PNG文件，并使用ImageMagick将图像拆分为单独的文件吗？

I'm having a problem where a PNG file that was created using the PDF export feature in OS X's Preview will display like an animated GIF in some browsers (Safari,Firefox) or display only the first page (Chrome) I'm having a problem where a PNG file that was