Sparanoid

Media Auto Hash Rename will rename any file (specific files can be ignored by file extension) during upload, with unique, low collision hashes. Hash characters and length can be configured for even lower collision rate.
More information please visit my <a href="https://sparanoid.com/work/media-auto-hash-rename/" rel="nofollow ugc">site</a>.
This plugin provides no configuration GUI to make it more easier to maintain with the future WordPress updates.
Currently there’re 3 constants you can configure in your <code>wp-config.php</code>, I recommend WP-CLI for maintaining these constants.
<ul>
<li><code>MAHR_LENGTH</code>: length of the random hashes, (default to <code>8</code>), longer can help reduce collision. Hashes at the length of 8 can be collision-free at the scale of 50,000 images).</li>
<li><code>MAHR_CHARS</code>: Characters used in hashes, default to <code>0123456789abcdefghijklmnopqrstuvwxyz_</code>, You can add more characters like uppercased alphabelts to dramatically reduce the collision without increasing the length of your filenames. But please note that this option can be dangerous if you’re not familer with general URI encoding. So if you don’t know what characters are allowed in a filename, just keep it untouched and use the default option.</li>
<li><code>MAHR_IGNORE</code>: File extensions to be ignored, default to <code>pdf, zip</code>, you can define a comma delimited list of file extensions to bypass renaming process of this plugin. All files that has the file extension you defined in the list will be ignored. Please note that:
<ul>
<li>File extensions must be defined without the leading peroid, for example: <code>'pdf, 7z, bmp'</code> works, <code>'.pdf, .7z, .bmp'</code> does not.</li>
<li>With (<code>'pdf, zip'</code>) or without (<code>'pdf,zip'</code>) space both work.</li>
<li>If you define your own ignore list, default ignore list will be discarded. For example, if you define <code>'7z'</code>, then <code>'pdf, zip'</code> will be processed during upload. You need to reapply these extensions with your own: <code>'7z, pdf, zip'</code>.</li>
<li>If you don’t need to ignore any files by its extension. define an empty array <code>[]</code> (without quotes) to this option: <code>define( 'MAR_IGNORE', [] );</code> to force process PDF and ZIP files.</li>
</ul>
</li>
</ul>

Media Auto Hash Rename

Rename media filename during upload with unique hash.

Scott Reilly

This plugin provides template tags that allow you to retrieve the name, path (relative or absolute), url, or fully marked-up link to a randomly chosen file or files in a specified directory.
Arguments to the functions permit you to limit what file(s) can be randomly selected based on a given set of file extensions. You can also explicitly specify files that should not be randomly selected.
This functionality can be useful for displaying random images/logos or including text from random files onto your site (writing excerpts, multi-line quotes, etc). Other ideas: random ads, random CSS files, random theme template selection.
Notes:
<ul>
<li>
If you want to actually display the name of the random file, be sure to ‘echo’ the results:

</li>
<li>
Unless you limit the file search to only include a particular extension (via <code>$extensions</code> argument), all files in the specified <code>$dir</code> will be under consideration for random selection
</li>
<li>
Can be run inside or outside of “the loop”
</li>
</ul>
Links: <a href="https://coffee2code.com/wp-plugins/random-file/" rel="nofollow ugc">Plugin Homepage</a> | <a href="https://wordpress.org/plugins/random-file/" rel="ugc">Plugin Directory Page</a> | <a href="https://github.com/coffee2code/random-file/" rel="nofollow ugc">GitHub</a> | <a href="https://coffee2code.com" rel="nofollow ugc">Author Homepage</a>
<h3>Developer Documentation</h3>
Developer documentation can be found in <a href="https://github.com/coffee2code/random-file/blob/master/DEVELOPER-DOCS.md" rel="nofollow ugc">DEVELOPER-DOCS.md</a>. That documentation covers the template tags and hooks provided by the plugin.
As an overview, these are the template tags provided by the plugin:
<ul>
<li><code>c2c_random_file()</code> : Retrieves the name of a random file from a specified directory and returns information based on the file.</li>
<li><code>c2c_random_files()</code> : Retrieves the name, path, or link to a specified number of randomly chosen files in a specified directory.</li>
</ul>
These are the hooks provided by the plugin:
<ul>
<li><code>c2c_random_file</code> : Filter to safely invoke <code>c2c_random_file()</code> in such a way that if the plugin were deactivated or deleted, then your calls to the function won’t cause errors in your site.</li>
<li><code>c2c_random_files</code> : Filter to safely invoke <code>c2c_random_files()</code> in such a way that if the plugin were deactivated or deleted, then your calls to the function won’t cause errors in your site.</li>
</ul>

Random File

Retrieve the name, path, or link to a randomly chosen file or files in a specified directory.

Media Auto Hash Rename vs Random File