It would look just like a flat photograph floating in the space on front, or behind the frame. The third, missing dimension of a photograph cannot be reconstructed by holographic process. It is a film similar to camera film, but of much higher resolution. Dichromate hologram is made of special gelatin emulsion sealed between two glass plates. It offers really bright and sharp imaging.
Embossed holograms are the lowest priced in large runs.
Embossed holograms often are multi-color. Color information is computer-generated before embossing process. Photo-polymer is relatively new material. It gives very bright image on a flexible surface. Our holographic sunglasses are made with photo-polymer.