/**
 * @since 2019-12-27 01:29
 * @author vivaxy
 */
export declare const FILTER_LENGTH = 1;
export declare enum FILTER_TYPES {
    NONE = 0,
    SUB = 1,
    UP = 2,
    AVERAGE = 3,
    PAETH = 4
}
export declare const unfilters: {
    [filterType in FILTER_TYPES]: (data: Uint8Array, bytePerPixel: number, prevUnfilteredLine: Uint8Array) => Uint8Array;
};
export declare const filters: {
    [filterType in FILTER_TYPES]: (data: Uint8Array, bytePerPixel: number, prevUnfilteredLine: Uint8Array) => {
        sum: number;
        filtered: Uint8Array;
    };
};