how to convert powerpoint into images

I want to conve开发者_如何学运维rt powerpoint into images when a user uploads it to my server. What is the best way of doing it?

I was using interop, but it seems to be working only on client side.

You can start PowerPoint with the /M switch and specify a macro. The macro should contain a "Save As Other Formats" command that saves to the image format you require - I'd suggest PNG or JPEG. The macro can also exit from PowerPoint when it completes.

PowerPoint might not run well on a server; it will probably leave a hung instance if it tries to display an error box without having an attached display. It will definitely give the best looking results.