Here’s one way to inject the custom field as the featured image caption with help of the post_thumbnail_html filter: add_filter( ‘post_thumbnail_html’, function( $html, $post_id ) { if( $html && $caption = get_post_meta( $post_id, ‘wpcf-bildunterschrift’, true ) ) $html .= sprintf( ‘<p>%s</p>’, sanitize_text_field( $caption ) ); return $html; }, 10, 2 ); Hopefully you can adjust … Read more
As linked to from the comments on your question, the post_gallery filter should help you here. Unlike a lot of other hooks though, you can’t filter the output that comes through from WordPress; you can only provide your own alternative output. This is slightly annoying, and results in you needing to build the gallery from … Read more
This is mostly a PHP general question about concatenating a function’s returned value with a (or many) string(s). The get_bloginfo function returns a string instead of echoing it directly. Thus you start off with: // First param value: stylesheet_directory // Using “template_url” also works unless you are using a child theme // In that case, … Read more
These days it is not really possible anymore to distinguish between mobile and other browsers, but you may try wp_is_mobile. There are plugins that try to do a better job. Then, if the user agent is mobile you may try to disable saving of the image, but there is no definite way to do this. … Read more
The filter you are using only stops jpeg compression. This does not prevent quality loss when resizing an image. Manually you would apply a sharpen filter afterwards to regain some crispyness in the image. WordPress doesn’t do that. However, WP does have the WP_Image_Editor class for image manipulation. It has some built-in methods, such as … Read more
function replaceImageMeta( $imagename ) { preg_match_all(‘/(alt|title|src)=(“[^”]*”)/i’,$imagename, $img);//var_dump( str_replace(“\””, “” , ( $img[2][0] ) ) ); list($width, $height, $type, $attr) = getimagesize( str_replace(“\””, “” , ( $img[2][0] ) )); $imgname = str_replace(“\””, “” , ( $img[2][0] ) ); return sprintf(‘<img src=”https://wordpress.stackexchange.com/questions/235051/%s” width=”%dpx” height=”%dpx” >’, str_replace(“\””, “” , ( $img[2][0] ) ), $width, $height); } So call … Read more
The email header is not the same as the <head> of an HTML document (even if that document is an email). So the question shouldn’t be how to display an image in the email header because the answer is that you can’t. Second, the same thing holds true for an HTML document. The <head> section … Read more
try using get_attached_media function and your current $postID $images = get_attached_media( ‘image’, $postID ); this will return a WP_Post object. If you want to get the url, it’s located in the guid key of the object. Use a foreach loop to retrieve them all. foreach( $images as $image ){ $src[] = $image->guid; } To use … Read more
In WordPress attachments are treated as posts, with their own titles, excerpts and metavalues. So if a post has an attachment there are two sets of metavalues, one for the post itself and one for the attachment. You are using update_post_meta( $post[‘ID’] … to store the url. So it is stored as a metavalue of … Read more
WordPress v4.4 introduced an additional image size named medium_large which is is 768px wide by default, with no height limit. There is no UI for the medium_large but the size can be changed by updating the options: /** * Updates the medium_large image size. * It’s only necessary to execute this code once. * Ideally … Read more