Aspose. Pdf. Kit is a .NET component for editing existing PDF files. You can also use it to add or remove digital signatures and encrypt or decrypt a PDF. It supports many useful features like PDF stamp creation, adding a CJK font in a form field, AcroForm, adding a watermark or logo, extracting or adding images and text, adding bookmarks, appending pages, and converting a PDF file to TIFF, BMP, PNG, and JPG image formats. It enables you to concatenate PDF files and allows adding or setting XMP Metadata to an existing PDF.