Originally Posted by Brad Grenz
So, we're agreed that a 48 FPS 3D version of The Hobbit is not possible under the current Bluray Spec
It's not possible currently unless you encode it into an existing Blu-ray video standard eg. 720p50 3D or 720p60 3D (or side-by-side with 1080i but that's probably against the spec even though it should work).
but couldn't you manipulate the 3D Bluray standard to create a 2D version at 48 fps? 3D Blurays basically pack two images into a single frame that the TV understands need to be displayed as alternating eyes, yes? So instead of encoding with alternating perspectives, you could encode with sequential images which would give you 48 FPS playback on a 3D TV, assuming you don't wear the 3D glasses. Maybe it would be too confusing to market a 2D HFR version on disc that requires a 3D capable player and TV, but it would be technically possible.
Well they could change the Blu-ray specs, to add support for extra video formats, which they are already looking at (the "format extension study task force").
Also, passive 3D TVs display both eye views simultaneously. Encoding 2D 48 fps you'd have the problem that the active TV shows each eye's view of 24 fps 3D content multiple times. eg. something like L1, R1, L1, R1, L2, R2... (obviously it depends on the TV/glasses), so if you encoded 2D 48 fps like that it would keep skipping back frames when shown on the active 3D TV, eg. something like frame 1, 2, 1, 2, 3, 4, 3, 4... (probably not quite that since 60/24=2.5). It might be easier to show 120 fps 2D content by encoding it as 720p60 3D if the active 3D TV only shows each eye view once
(again probably won't work with passive 3D TVs, unless they altered them).
The best existing format in the standard specs to encode 48 fps 2D onto Blu-ray is either 720p50/720p60 or 1080/50i or 1080/60i (some players/TVs in the US wouldn't be compatible with 720p50 and 1080/50i).