1. A computer-implemented method of producing a 3-D image file, the method comprising the steps of: generating graphics instructions which define image-related characteristics of a first 3-D image frame, wherein a graphics instruction can be used to instruct a display software to render a characteristic of a 3-D image frame; generating image commands corresponding to the graphics instructions the image commands including graphics instruction reference data and graphics instruction argument data; and transferring the image commands to an output 3-D image file; wherein the output file includes information to instruct the display software to display the original 3-D image frame so as to be viewable from multiple viewpoints.