const
  LIB_NAME = 'actvcmp.dll';

function Decompress(src, dst: Pointer): word; cdecl; external LIB_NAME name 'Decompress';
function DecompressedSize(src: Pointer): word; cdecl; external LIB_NAME name 'DecompressedSize';
function CompressedSize(src: Pointer): word; cdecl; external LIB_NAME name 'CompressedSize';
function Compress(src, dst: Pointer; Length: word): word; cdecl; external LIB_NAME name 'Compress';