Abstract: A meta-crystal slab includes photonic structure with an input surface and an output surface, and a plurality of first voxels with a first permittivity and a plurality of second voxels with a second permittivity not equal to the first permittivity disposed between the input surface and the output surface. The photonic structure has a periodicity greater than an operating photonic wavelength ‘?’ for general convolution by the photonic structure and the photonic structure is configured to provide an output image with a convolution of an input image.