how to change image size and update BD automatic ?

Hello,

I’m looking for a solution to do this :

there is already 300 posts with images, I never changed the size in options-media.php, most of images are used in medium size, linked to the original size for visitors.

But I want to change all the images’s size already published on the post, but without doing manually.

Is it possible to have a plugin can do that automatically ?

like that :

• change the size of the thumbs, that I can do it here manually : options-media.php
• recreate all the thumbs in the right size,
• automatically change the size of the image already used in posts, in the DB

I find thoses plugins :
Regenerate Thumbnails : perfect to generate news thumbs
Thumbnail Cleaner : perfect to clean all of the old ones,

but nothing to uptodate the DB,

Do you have an idea ?

Thanks for help,