GroupDocs.Watermark for .NET is a powerful API for managing watermarks in the various documents formats such as PDF, DOCX/DOC/RTF, PPTX/PPT, XLSX/XLS, JPG, PNG, TIFF, GIF and many others....document; Attach watermark to all images in a particular section, page...particular frames of a multi-framed image; Allocate hidden watermark to...