We try to use the Aspose.Slides Java Library 17.3 to create thumbnails of existing presentations.
Thanks for inquiring Aspose.Slides.
I have observed your comments and like to share that we are continually heading towards improving the performance of Aspose.Slides for Java API. If you use Aspose.Slides for .NET API, it has got improved performance ration considering to Aspose.Slides for Java.
For your other question related to performance and working of Aspose.Slides for Java, I request you to please share the source presentation, working sample code, java details and snapshots of memory usage. We will try reproducing the issue on our side to help you further in this regard.