This particular issue was caused by an environment missing GD. After installing GD on the server, the issue was resolved. Of course you will need to go back and re-submit your thumbnails to have correct cropping, or use a plugin to retroactively recreate your thumbnails.
For a one-off batch operation, you can use this plugin: http://wordpress.org/extend/plugins/add-from-server/ But first you should figure out why they don’t show up in the first place. Maybe complain to the theme developer.
You can use has_post_thumbnail() as condition and change output accordingly. Example from Codex: if(has_post_thumbnail()) { the_post_thumbnail(); } else { echo ‘<img src=”‘.get_bloginfo(“template_url”).’/images/img-default.png” />’; }
A MYSQL Query cannot delete the files themselves. You will have to use wp_delete_attachment(). The following is a proof-of-concept for you to alter how you please. The featured image is stored in postmeta as _thumbnail_id. wp_delete_attachment() does the rest for you. <?php /* Plugin Name: Delete All Featured Images Description: Delete all featured images by … Read more
get_children will return an associative array of posts […] with post IDs as array keys, or an empty array if no posts are found. This statement $attachment_id => $attachment is the same as the more commonly used $key => $value. Using this command echo ‘<pre>’.print_r($attachments,true).'</pre>’; we get the following: resumed version of a get_children with … Read more
This should work: You could use: add_image_size( ‘category-thumb’, 220, 9999 ); //220 pixels wide (and unlimited height) and then to display: if ( has_post_thumbnail() ) { the_post_thumbnail( ‘category-thumb’ ); } This will create a thumbnail size of 220 by “unlimited”… Set the featured image on the post, then use the display code in your theme … Read more
Remember that custom image sizes are NOT applied retroactively to images already uploaded. Use a plugin like Regenerate Thumbnails or similar to generate them.
The ID of the featured image is stored under the meta key _thumbnail_id, so we can do a query for a single post that has this key: $args = array( ‘posts_per_page’ => 1, ‘meta_key’ => ‘_thumbnail_id’, ‘cat’ => $cat_id ); $latest_thumb = new WP_Query( $args ); if( $latest_thumb->have_posts() ) return get_the_post_thumbnail( $latest_thumb->post->ID );
There are lots of plugins that do this one way or another including: http://wordpress.org/extend/plugins/regenerate-thumbnails/ http://wordpress.org/extend/plugins/dynamic-image-resizer/ I wouldn’t recommend reinventing the wheel. If you’re particularly worried about it, you might looking into TGM Plugin Activation to suggest to people in the Dashboard that they install and use the plugin.
Use the filter post_thumbnail_html. The callback takes 5 parameters, the first ($html) is the one that’s returned and that we modify, and the others can be helpful to build the modification. add_filter( ‘post_thumbnail_html’, ‘add_tag_to_featured_wpse_95469’, 10, 5 ); function add_tag_to_featured_wpse_95469( $html, $post_id, $post_thumbnail_id, $size, $attr ) { $modify = str_replace( ‘<img’, ‘<img itemprop=”photo”‘, $html ); return … Read more