Kiet Huynh

This plugin will help to replace broken images in posts and pages with a default image.

Replace Broken Images

It's OK

Alternate image with a default image if source image is not found on posts and pages.

Cheung Tat Ming

WP-LinkCheck is a lightweight plugin ability to check all image sources are broken inside your WordPress blog, it check the http header by server response ,it don’t have to download the images to boost the performace and bandwidth.
Repersent the result to SlickGrid utilizes virtual rendering to enable you to easily work with 50000+ of items without any drop in performance. 
WP-LinkCheck is safe to use. It will NOT make any database change (create table, modify table etc…), and NOT to create any cache files to keep your WordPress directory clean.
If the broken links are found, WP-LinkCheck will NOT do any modication / deletion to the content, everythings is under your control, you can simply click the post title and correct the url by yourself.
Ability to handle several HTTP Error in broken image includes: 
<ul>
<li>403 Access Denied/Forbidden</li>
<li>404 File Not Found</li>
<li>410 Gone</li>
<li>500 Internal server error</li>
</ul>
<h3>Future Development</h3>
<ol>
<li>Support youtube movie checking by Youtube API.</li>
<li>Options to filter record by a period.</li>
</ol>
Any Suggestion? Please go to my Blog : http://blog.miawork.com/?page_id=2190 and leave a suggestion.

WP-LinkCheck

WP-LinkCheck is a lightweight plugin ability to check all image sources are broken inside your WordPress blog.

Replace Broken Images vs WP-LinkCheck