Thumbnails Manager helps you to manage your thumbnails within the administrator panel. You can define a default ratio for thumbnail creation, rename, change the description or even delete your thumbnails.
This is the very first time I release one of my own plugin. Maybe because it is a little bit more finished than the previous ones even if I can?t say I spent a lot of time on this one.
Well? In other words, be indulgent and please give me helping comments and any wish for the next version.
A small list of features:
<ul>
<li>Change the default ratio for the thumbnails.</li>
<li>Display images by pages.</li>
<li>Rebuild thumbnails.</li>
<li>Rename and change the description.</li>
<li>Resize of thumbnails.</li>
<li>Delete of images.</li>
<li>Thumbnails creation size strategy: scaling, maximum size, fixed size</li>
</ul>
New in v0.7:
<ul>
<li>Thumbnails creation size strategy: scaling, maximum size, fixed size</li>
<li>A bug correction (impossible to save ratio value)</li>
</ul>

Thumbnails Manager

Thumbnails Manager helps you to manage your thumbnails within the administrator panel. You can define a default ratio for thumbnail creation, rename,  …

Yslo

Empty spaces and special characters can create some problems.
<h4>Features</h4>
<ul>
<li>Improved default function <a href="https://codex.wordpress.org/Function_Reference/sanitize_file_name" rel="nofollow ugc">sanitize_file_name()</a></li>
<li>Remove latin special characters used in file name</li>
<li>Make file name lowercase</li>
</ul>

WP Sanitize File Name Plus

Sanitize file names and enhance security.

Thumbnails Manager vs WP Sanitize File Name Plus