import { AnnotationBase } from "./AnnotationBase";
/**
 * Represents an annotation of a type that is not currently supported by DsPdfJS.
 *
 * An instance of this type cannot be created by user code.
 * Instances of this type will be created if a PDF containing annotations
 * of unsupported types is loaded into a {@link PdfDocument}.
 */
export declare class UnknownAnnotation extends AnnotationBase {
    /**
     * Gets the annotation type according to the PDF specification.
     */
    get subtype(): string | null;
}