Tahir Yasin

Awesome Watermark is a WordPress plugin that allows you to protect your images by adding text/image watermark on them. You can add different watermarks to different image sizes.
<h3>Features</h3>
<ul>
<li>Separate watermark for every image size</li>
<li>Supports both Text & Image watermark</li>
<li>Custom watermark position</li>
<li>Tiled/Textured watermarks</li>
<li>Control output image quality</li>
<li>Rotate watermark at any angle</li>
<li>Backup option for original images </li>
<li>Preview watermark</li>
<li>Supports Woocommerce product images</li>
</ul>

Awesome Watermark

Apply text or image watermark to any WordPress image and thumbnails sizes.

ip4368

This plugin allows to add a watermark on the images uploaded.
It make use of .htaccess, so all images that are uploaded or to be upload will all have the watermark. Your source images will not be affected, and after you delete/deactivate your plugin, all watermark will disappear. This plugin also work with @2x images that use on retina display or high resolution screen devices.
With this plugin, you may :
<ul>
<li>change the size of the watermark proportion to the images width.</li>
<li>change the opacity of the watermark, you are recommended to upload a png with solid color, as you may adjust the opacity after you upload.</li>
<li>(soon)set the position of the watermark and the offset position.</li>
<li>(soon)choose repetitive mode to display your watermark.</li>
<li>(soon, but later)choose the path that images in that path will have watermark.</li>
</ul>
The watermark is only visible if you try to download/view the images from a web browser.
You have to know that :
<ul>
<li>you need to be able to create a htaccess file in your uploads directory.</li>
<li>you need the GD library.</li>
<li>works only with JPG/JPEG/PNG files.</li>
</ul>
Available languages in :
<ul>
<li>English</li>
</ul>

htaccess Watermark

This plugin allows to add a watermark on your images uploaded.

Awesome Watermark vs htaccess Watermark