C# .NET API To add, search and remove image & text-based watermarks from documents: PDF, Word, Excel, Presentations, Visio, email and image file formats....PPSM, POT, POTM, POTX, PPTM Visio: VSD, VDX, VSS, VSSX, VSX, VST...& Footer PowerPoint : Shape Visio : Shape Raster Image : Text...