export interface SeparatedChannels {
    color: Uint8Array;
    alpha: Uint8Array;
}
export declare function unfilterScanlines(data: Uint8Array, bytesPerRow: number, height: number, bytesPerPixel: number): Uint8Array;
export declare function separateAlphaChannel(compressed: Uint8Array, width: number, height: number, colorType: number, bitDepth: number): SeparatedChannels;
export declare function expandPalette(compressed: Uint8Array, width: number, height: number, bitDepth: number, palette: Uint8Array, transparency?: Uint8Array): SeparatedChannels;