In a print shop system including a plurality of printers and a print shop management server which manages print jobs, an improved method is described for detecting color components in a document page for purposes of assigning the document to appropriate printers for printing. First, each page element is analyzed without rasterizing the page. If a raster image is colored, its location and size are added to an image information list. If a non-raster graphical element overlaps a raster image previously stored in the image information list, the overlapped raster image is removed from the list. After analyzing all page elements of the page, if any raster image remains in the image information list, the page is marked as colored. Otherwise, the page is rasterized to detect colored using a conventional method. The resolution used for page rasterization may be controlled by a user.