Samuel Wood (Otto)

Normally when you upload an image to a WordPress site, it creates several differently sized versions of the image automatically. Themes can define custom image sizes as well, increasing the amount of images generated on your server.
This plugin changes the way WordPress creates images to make it generate the images only when they are actually used somewhere, on the fly. Images created thusly will be saved in the normal upload directories, for later fast sending by the webserver. The result is that space is saved (since images are only created when needed), and uploading images is much faster (since it’s not generating the images on upload anymore).
“Pretty” permalinks must be enabled for this plugin to function.
Note: This plugin does not work on multisite setups, due to the way WordPress handles file serving in such situations (with ms-files.php).
Want regular updates? Become a fan of my sites on Facebook! 
http://www.facebook.com/apps/application.php?id=116002660893 
http://www.facebook.com/ottopress
Or follow my sites on Twitter! 
http://twitter.com/ottodestruct

Dynamic Image Resizer

Make your images change sizes dynamically.

Tekod lab.

This plugin is solution for well known flaw in WordPress architecture: 
automatic resizing uploaded images in each of registered media sizes.
Although price of hosting space is low and we have gigabytes available that can be issue if you have dozen 
(or more) registered sizes and because of that your backup files became larger than 10Gb. 
Sooner or later you will be in situation to download (or even worse – to upload) that backup file.
Our analysis shows that vast majority of resized thumbnails are not used anywhere in website. 
For typical theme with WooCommerce and additional 3 custom media sizes that percentage can be over 90%, 
with 6 custom media sizes it is over 96% !!!
Because of that developers are often uncomfortable with registering more media sizes trying to find 
some workarounds or violating design to accommodate existing similar sizes.
Purpose of this plugin is to eliminate that overhead and allow developer to register as many sizes as he needs.
It will intercept uploading process to prevent creation of thumbnails and intercept getters 
(wp_get_attachment_image_src(), get_the_post_thumbnail_url(), the_post_thumbnail(),…) to create thumbnail if needed. 
Additionally, it will register in database each created thumbnail allowing WordPress to delete it automatically 
when parent image is deleted.
<h3>Usage</h3>
At “Settings” tab of this tool you can pick individually for which size you want to enable or disable this functionality. 
Typically, you will enable it for all sizes.
Button “Delete” on “Utilities” tab will remove all thumbnails for sizes that are handled by this plugin. 
That will significantly reduce size of your “uploads” directory allowing new thumbnails to be recreated on demand.
Button “Regenerate all thumbnails” will remove existing and create new thumbnails for all your uploaded images.
Video demonstration:
<iframe loading="lazy" class="youtube-player" width="750" height="422" src="https://www.youtube.com/embed/hfbkbM-1dlY?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>
<h3>Contact</h3>
Please, send bug reports and feature requests to <a href="mailto:office@tekod.com" rel="nofollow ugc">office@tekod.com</a>

FWS On-Demand-Resizer

Smart on-demand image resizer for WordPress.

Dynamic Image Resizer vs FWS On-Demand-Resizer