This is the question our users sometimes ask us. I think the time has come to dwell on this topic. If you make a simple test and convert one same file with FlashSpring Pro and Server you’ll see that the conversion with FlashSpring Pro is much faster and now I’ll tell you why.

FlashSpring products use PowerPoint application to access some properties of the PowerPoint presentation using COM Automation technique. Automation allows one application (for example FlashSpring) to control another application (PowerPoint) via defined set of interfaces.

FlashSpring Pro works as a PowerPoint add-in. It means it is located in PowerPoint application address space being a part of PowerPoint process. In this case the interaction between PowerPoint and FlashSpring Pro doesn’t require switching between processes and all calls from FlashSpring Pro to PowerPoint are executed without overhead.


FlashSpring Server EXE application is implemented as a standalone process. Thus, when FlashSpring Server calls some PowerPoint method, Windows operating system passes parameters from FlashSpring process to PowerPoint process, switches from FlashSpring to PowerPoint, executes the called method, then passes the result back from PowerPoint to FlashSpring. An overhead for switching between processes and passing parameters is quite big and this increases the time of conversion.

Our developers made some tests.

100 000 calls of simple method (for example, the method for getting PowerPoint version) take 46 seconds when they are called from external process and take 46 milliseconds when they are called within PowerPoint. So, an overhead for method call performed from one process to another is about 1000 times bigger than internal method call. This is a time required to perform switching between processes.

The similar situation occurs when FlashSpring Server COM Component is used. In this case even if it resides in your application address space and is a part of your application it still involves inter-process interaction with PowerPoint.


FlashSpring developers have made much research on optimizing the speed of conversion and succeed in it. Any case, FlashSpring, both Pro and Server, always provide you with high quality conversion. Our software will do it Easy and Fast!

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