An example function based on this filter hook that regulates the size of the images, based on you having phpThumb. (http://phpthumb.sourceforge.net - phpThumb is a free library you can download and install on your php webserver. Installation and configuring phpThumb is beyond scope of this, sorry).
add_filter('pre_link_image','pre_link_image_add_thumb'); function pre_link_image_add_thumb($img_url){ // set our width value $width = 400; // set a height value? update it in the params line below add "&h=$height". we only are using width though. // $height = 80; // this points to our specific location for phpThumb $thumb_file = "http://yourserver.com/phpThumb/phpThumb.php"; // here we specify a width and the img src recvd by this function $thumb_params = "w=$width&src=$img_url"; // and now we make our "new" img url $new_img_url = $thumb_file . "?" . $thumb_params; // and now we return it! return $new_img_url; }
Basically, you can do stuff with/to the img_url entered by the user when they add/edit a link. this info is then written to the database, and now is what the user sees when going back to edit that link. The other end of this would be a "post_link_image" function, but i don't believe the hooks exist yet on that side.
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