MyWebsiteAdvisor

ChrisHurst

This plugin allows you to watermark your previously uploaded images using a PNG image file with transparency as well as text signature. 
The user friendly settings page allows for control over the appearance of your watermark. 
You can set your watermarks to always be a specific percentage of the target image. 
This plugin will add the watermarks to ALL of the images in your WordPress uploads directory.
Please BACK UP all of your uploads via FTP before using this plugin!
<a href="http://mywebsiteadvisor.com/plugins/bulk-watermark/" rel="nofollow ugc">Upgrade to Bulk Watermark Ultra</a> for advanced 
watermark features including:
<ul>
<li>Fully Adjustable Text and Image Watermark Positions</li>
<li>Adjustable JPEG Image Output Quality</li>
<li>Highest Quality Watermarks using Image Re-sampling rather than Re-sizing</li>
<li>Lifetime Priority Support and Update License</li>
</ul>
Check out the <a href="http://www.youtube.com/watch?v=XkFXBjfzw2I&hd=1" rel="nofollow ugc">Bulk Watermark Plugin for WordPress Video Tutorial</a>:
<iframe loading="lazy" class="youtube-player" width="750" height="422" src="https://www.youtube.com/embed/XkFXBjfzw2I?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&hd=1&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>
Developer Website: http://MyWebsiteAdvisor.com/
Plugin Support: http://MyWebsiteAdvisor.com/support/
Plugin Page: http://mywebsiteadvisor.com/plugins/bulk-watermark/
Compare Watermark Plugins: http://MyWebsiteAdvisor.com/tools/wordpress-plugins/watermark-plugins-for-wordpress/
Video Tutorial: http://mywebsiteadvisor.com/learning/video-tutorials/bulk-watermark-tutorial/
Requirements:
<ul>
<li>PHP v5.0+</li>
<li>WordPress v3.3+</li>
<li>GD extension for PHP</li>
<li>FreeType extension for PHP</li>
</ul>
To-do:

Bulk Watermark

Adds an image and/or text watermark to all uploaded images, using PNG images with transparency.

Protect Uploads

The uploads directory is where the files of the WordPress library are stored. Unfortunelty, this directory is not protected. A person who wants to see all your library could list it instantly going to : http://yourwebsite/wp-content/uploads . This plugin will hide the content by adding an index.php file on the root of your uploads directory or by setting an htaccess which will return a 403 error (Forbidden Access).
<ul>
<li>Depending on your server setting, the htaccess option could be disabled.</li>
</ul>
New Features in Version 0.6.0:
<ul>
<li>Image Watermarking: Add text watermarks to your uploaded images with customizable position, opacity, and font size.</li>
<li>Right-Click Protection: Prevent users from right-clicking to download or save your images.</li>
<li>Password Protection: Secure individual media files with passwords. Multiple passwords can be set for each file with custom labels.</li>
<li>Access Logging: Track who accesses your password-protected files with detailed logs including IP address and user agent.</li>
</ul>
Available languages:
<ul>
<li>English</li>
<li>Français</li>
<li>Español</li>
<li>Italian (thanks to Marko97)</li>
</ul>

Do not download. The plugin has been changed not too long ago and it now infects your wordpress installation, and possible spreads itself to other sites if you are on shared hosting.

It's a virus

Protect your uploads directory. Prevent browsing, add watermarks, disable right-click, and password-protect files. For more information, visit protect …

Bulk Watermark vs Protect Uploads