A scanned image of Keykode from a piece of unexposed, developed 35 mm Eastman Kodak motion picture color negative. All of these slices are from the same side of the same piece of negative, cropped and stacked for simplicity. (A) Human-readable Keykode number (the number to the far right advances by one for each 16 frames of 35 mm film or 20 frames of 16 mm film).