WordPress Gravatar: Notes

Replace Gravatar with Local Image

add_filter( 'get_avatar', 'bubdev_get_local_avatar', 10, 5 );
/**
 * Replace Gravatar
 * 
 * Replaces specific user gravatar with local image. Disables all other user
 * gravatars on the frontend.
 */
function bubdev_get_local_avatar( $avatar, $id_or_email, $size, $default, $alt ) {

  if ( is_admin() ) return;

  $user_mail = 'some@email.net';
  $att_url = wp_upload_dir()['baseurl'] . '/someone.jpg';
  $att_id = attachment_url_to_postid( $att_url );
  $att_alt = get_post_meta( $att_id, '_wp_attachment_image_alt', true );
  
  if ( $id_or_email && $id_or_email === $user_mail ) {
    $markup = '<img src="' . $att_url . '" class="avatar photo" width="' . $size . '" height="' . 
      $size . '" alt="' . $att_alt . '">';

    return $markup;
  }

  return false;
}

Genesis Framework Gravatar Modifications

//* Modify the size of the Gravatar in the author box
add_filter( 'genesis_author_box_gravatar_size', 'bub_author_box_gravatar' );
function bub_author_box_gravatar( $size ) {
  return 144;
}


//* Modify the size of the Gravatar in the entry comments
add_filter( 'genesis_comment_list_args', 'bub_comments_gravatar' );
function bub_comments_gravatar( $args ) {
  $args['avatar_size'] = 96;
  return $args;
}