Stereoscopic image generating device and method of operating the same

A method of operating a stereoscopic image generating device communicating with a rendering server device, the method comprising:

• obtaining first tracking data by tracking a motion of a user during a reference time interval;
• obtaining second tracking data by tracking a viewpoint of the user during the reference time interval;
• providing the first tracking data to the rendering server device;
• generating, by the rendering server device, one or more focus image data by downscaling original image data corresponding to the first tracking data;
• receiving, from the rendering server device, the one or more focus image data generated by downscaling the original image data and filter data used when the rendering server device performs the down-scaling on the original image data;
• extracting one or more areas corresponding to the tracked viewpoint from each of the one or more focus image data based on the second tracking data;
• generating multifocal virtual reality (VR) image data by up-scaling the extracted one or more areas based on the filter data;
• and
• visually providing, by a display device of the stereoscopic image generating device, the multifocal VR image data to the user.