AMP_Image_Dimension_Extractor::register_callbacks PHP Метод

    private static function register_callbacks()
    {
        self::$callbacks_registered = true;
        add_filter('amp_extract_image_dimensions_batch', array(__CLASS__, 'extract_by_downloading_images'), 999, 1);
        do_action('amp_extract_image_dimensions_batch_callbacks_registered');
    }