TSR Watermark Image is a free (for personal use) tool which makes it easy to add a digital watermark to your images.
Your watermark can be text, or an image. Choose the format option and you're able to customise the text's font, colour and angle, add a border, chisel or embossed effect, and automatically add the text to your file's EXIF "Copyright" tag. And of course you can set both text and image-based watermarks to use your choice of transparency level.
The program can also carry out other useful batch processing tasks. By default it will automatically rotate the image based on EXIF information, for instance, so that your watermark is always displayed the right way up. You're able to resize the imported images, too. And once the watermark has been added, TSR Watermark Image can export the image as a BMP, GIF, JPEG, PNG or TIFF file.
Please note, TSR Watermark Image is free for personal use only. Business users may test the program for 30 days, but to continue using it after that they must purchase a licence. Prices start at $29, and you can read more at the Watermark Image site.