TMM Technology

A WordPress plugin for client-side uploaded images resize (to do it client-side instead of backend-side and minimize the backend performance hit).
<h3>Settings</h3>
Plugin settings are located under “Media” tab (“Resize before upload”), there you can configure:
<ul>
<li>Max image size in pixels (The images bigger than this threshold are scaled down to it);</li>
<li>Use WP-compat (old) assets uploading script.</li>
<li>A setting to enable / disable on front end / admin part separately.</li>
</ul>
<h3>Bug reports / Questions / Suggestions</h3>
<a href="mailto:wp@tmm.ventures" rel="nofollow ugc">wp@tmm.ventures</a>

Resize Image Before Upload

A WordPress plugin for client-side uploaded images resize (to do it client-side instead of backend-side and minimize the backend performance hit).

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This plugin enables you to automatically resize every user-posted image which is larger than given dimensions. Original plugin writen by <a href="http://www.ncode.nl/vbulletinplugins/" rel="nofollow ugc">Jorrit Schippers</a> for vBulletin.
Some features:
<ul>
<li>No resizing</li>
<li>Enlargement in the same document</li>
<li>Enlargement in the same window</li>
<li>Enlargement in a new window</li>
<li>Enlargement in modal window</li>
<li>Any JavaScript Framework is not required</li>
</ul>
It also adds an information bar (which is not displayed when the image is too small) giving information about the original dimensions and filesize.
Localization:
<ul>
<li>Belorussian (be_BY) – <a href="http://www.fatcow.com/" rel="nofollow ugc">FatCow</a></li>
<li>Arabic (ar_AR) – <a href="http://linuxawi.com/" rel="nofollow ugc">ZAH3R</a></li>
<li>Japanese (ja) – <a href="http://blog.osakana.net/" rel="nofollow ugc">osakanataro</a></li>
</ul>

nCode Image Resizer

This plugin enables you to automatically resize every user-posted image which is larger than given dimensions.

Resize Image Before Upload vs nCode Image Resizer