Y and AP compression filters yabba applies Y compression to its input whap applies AP compression to its input whap and unwhap run at about the same speed as UNIX compress and uncompress, which use LZW coding\; yabba and unyabba are two to three times slower. AP and Y compression are typically 10-20Illegal seekore effective than LZW compression in the same amount of memory. Y coding, unlike LZW coding and AP coding, is unpatented.