 Filters receive the spool file data as input, perform document processing, rendering and PDL post-processing, and then output PDL data for the printer to consume.Filters can perform a single function such as watermarking a page or doing color transformations or they can perform several print processing functions on specific document parts individually or collectively and then convert the spool file to the page description language supported by the printer.Windows Vista also provides improved color support through the Windows Color System for higher color precision and dynamic range.