Bill Erickson

<p>When you upload an image, WordPress will automatically scale/crop it to many different sizes. If you’re not happy with the auto-crops, use this plugin to upload an alternative image.</p>
<p>If you have images showing up in your theme already, there’s nothing you need to do after activating this plugin. All WordPress functions that provide the thumbnail should now automatically work with your override image.</p>
<p>This plugin will add a metabox to every post type and allow you to modify every image size (built-in and custom ones added using add_image_size). You can use two filters to change these (image_override_post_types and image_override_sizes). For examples, see the documentation.</p>
<p><a href="https://github.com/billerickson/Image-Override/wiki" rel="nofollow ugc">Documentation</a></p>
<p><strong>No support will be provided by the developer</strong></p>


Image Override

Allows you to override WordPress' auto generated thumbnails.

finnj

<p>Frontier Set Featured will set featured image from images in the post if no featured image is set by the user.</p>
<h4>Main Features</h4>
<ul>
<li>If no Featured Images is set on save, the plugin will:
<ul>
<li>Select the first image that is uploaded to the post, and set it as Featured Image</li>
<li>If still no Featured Image, select the first image from the post content, and set it as Featured Image</li>
</ul>
</li>
<li>The will work both from admin interface & frontend.</li>
</ul>
<p>Note: Only images from the media library can be used as featured images (as per WordPress standard).</p>
<h4>Frontier plugins</h4>
<ul>
<li><a href="https://wordpress.org/plugins/frontier-post/" rel="ugc">Frontier Post</a>  – Complete frontend management of posts</li>
<li><a href="https://wordpress.org/plugins/frontier-query/" rel="ugc">Frontier Query</a>  – Display lists and groupings of posts in post/pages and widgets.</li>
<li><a href="https://wordpress.org/plugins/frontier-buttons/" rel="ugc">Frontier Buttons</a>  – Full control of tinymce toolbars and buttons buttons</li>
<li><a href="https://wordpress.org/plugins/frontier-set-featured/" rel="ugc">Frontier Set Featured </a>  – Set featured image aut. based on post images </li>
<li><a href="https://wordpress.org/plugins/frontier-restrict-media/" rel="ugc">Frontier Restrict Media </a>  – Restrict media access to users own media</li>
<li><a href="https://wordpress.org/plugins/frontier-restrict-backend/" rel="ugc">Frontier Restrict Backend </a>  – Restrict access to the backend (wp-admin)</li>
</ul>


Frontier Set Featured

Frontier Set Featured will set featured image from images in the post if no featured image is set by the user.

Image Override vs Frontier Set Featured