I have a number of old-time stereoscope cards, each with two pictures. I tried scanning a few, and using a graphics program to make a single JPG for each pair, with the pictures side-by-side. I loaded the finished JPGs on a server.
I can view the pictures just fine via DLNA on my Panasonic GT50 3D HDTV. When displayed, the little "2D" symbol pops up in the corner, just as it does for all pictures. But nothing I've tried displays the picture in 3D -- all I ever see is just the pair of pictures side-by-side, just as I prepared on the JPG.
But what is the magic to make them displayed as 3D? I tried using the settings to try to force the display into 3D, without success. Is there a special format, or pixel ratio, or some special EXIF format or something else that the TV will recognize to tell it to attempt a 3D display?