A metadielectric nanostructure with narrow cavities is proposed, behaving as a reflective color filter for TM-polarized light while as a broadband reflector for TE-polarized light. By varying the cavity depth or changing the incident light polarization, reflective colors of the proposed structure cover the entire visible spectrum conveniently. In particular, the reflections of this proposed structure show good angular tolerance up to 50° for both polarizations. Furthermore, it can display colors even with two grating slits, which shows high printing resolution up to 70555 dpi, having great potential for applications of a large area color imaging and anticounterfeiting devices.