Patent ID: 8537425

Claim:
A method for identifying and trapping a frame buffer pixel, the frame buffer pixel associated with at least two display list objects, the method comprising: setting a first bit in a multi-bit flag associated with the frame buffer pixel when rendering the frame buffer pixel to a frame buffer; determining a value for a second bit in the multi-bit flag associated with the frame buffer pixel by: setting the second bit in the multi-bit flag, if the frame buffer pixel of a first associated display list object is a non-constant color pixel, resetting the second bit in the multi-bit flag, if the frame buffer pixel of the first associated display list object is a constant color pixel and if the first display list object is opaque, setting the second bit in the multi-bit flag, if the frame buffer pixel of a second associated display list object is a non-constant color pixel, or if the second associated display list object is non-opaque, resetting the second bit in the second multi-bit flag, if the frame buffer pixel of the second associated display list object is a constant color pixel, and if the second associated display list object is opaque, and identifying the frame buffer pixel as a candidate for trapping if the second bit in the multi-bit flag associated with the frame buffer pixel has been set or if the second bit in the multi-bit flag associated with at least one pixel neighboring the frame buffer pixel has been set; and trapping the identified frame buffer pixel, wherein the trapping is performed on one or more of a computer and a printing device.