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//////////////////////////////////////////////////////////////
///////// AUTO ATTACHMENT TITLE, ALT AND DESCRIPTION
//////////////////////////////////////////////////////////////
add_action( 'add_attachment', 'ced_add_image_meta_data' );
function ced_add_image_meta_data( $attachment_ID ) {

 $removes = array('big', 'small', 'header', 'featured', 'grid');

 $filename   =   $_REQUEST['name']; // or get_post by ID
 $withoutExt =   preg_replace('/\\.[^.\\s]{3,4}$/', '', $filename);
 $withoutExt =   str_replace($removes, '', $withoutExt);
 $withoutExt =   str_replace(array('-','_'), ' ', $withoutExt);

 $my_post = array(
   'post_title' => $withoutExt,  // title
   'ID'           => $attachment_ID,
   'post_content' => $withoutExt,  // description
 );
 wp_update_post( $my_post );
 // update alt text for post
 update_post_meta($attachment_ID, '_wp_attachment_image_alt', $withoutExt );
}