ImagePDF is command-line software that simplifies and enhances the conversion of raster image files to PDF files. Associated text data can be imported into the PDF files. Supported formats include BMP, DCX, JPEG, PCX, PNG, and TIFF.
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.