Greg - SiteOrigin

A lot of themes ship with Timthumb because it allows their users to start using the theme without rebuilding thumbnails.
Secure Image Resizer offers a far more secure alternative. It allows theme developers to rely on WordPress’ own image resizing functionality using <code>add_image_size</code> and <code>get_the_post_thumbnail</code>.
When get_the_post_thumbnail is called, Secure Image Resizer checks if the requested image size exists. If the image doesn’t exist it dynamically creates the resized version. It works in the background, with no front end functionality.
Theme developers can either bundle this plugin into their themes, or suggest that their users install it.
It also includes 2 functions <code>so_resize_custom</code> and <code>so_resize_custom_html</code> to do dynamic image resizing using Imagick. Great for theme developers.
Please Note: This is an early release of Secure Image Resizer. Please use it, try and break it and report any bugs to me support@siteorigin.com so I can quickly fix them and work towards version 1.0.

Secure Image Resizer

A very simple and secure image resizer. It adds dynamic resizing so you don't need to regenerate thumbnails when you install a new theme.

Blogestudio

Pau Iglesias

For each image uploaded WordPress generates several versions with different sizes. These images will be inserted 
in the post content using the visual editor selecting the right format size for the current theme, so that 
images can be displayed correctly in the theme layout avoiding the overflow to the sidebars or another elements.
These images are now part of the content, and are harcoded in posts independently to any change in the design 
or behavior of the blog.
Therefore, when switching your theme to another theme smaller, or the new theme is very big respect the old 
layout, may be these images do not fit perfectly with the new design.
For these cases the purpose of this plugin is the searching in the post content of images with the old image sizes 
(that result bad sizes for the current theme) and replace it for the right image format: thumbnail, medium, large, 
full or custom format size.
The process is simple and consists of three steps. The first step is a form to introduce the width to find, or the 
period between two widths separated by an hyphen (-) with max 100 points of difference. Optionally you can enter 
a custom post type, or leave blank for the ‘post’ post type.
In the next step present the coincidence or multiple coincidences for each post, with the old html code in grey color, 
and in black the replacement, and also the new image is displayed. For each item there is a checkbox (by default checked) 
that you can uncheck if the result is wrong or an exception.
Finally, at the end of the list, a submit button can perform these changes. Before this final step, is advisable to 
backup your posts table.

Replace Content Image Size

What a simple and effective plugin to get the job done.

I was able to replace old Image Sizes to the New Image sizes with one click.

And before changing the sizes, it gave me preview for all OLD image html tags and the new tags will be...

Thank you so much for the great plugin!

Great work Pau Iglesias!


Gets the Job Done, Perfectly!

Find images displayed in posts content and change the format size, very useful when you change the blog theme.

Secure Image Resizer vs Replace Content Image Size