HDTV Expert – 3D over broadcast digital TV: Can it be done right now?
By Pete Putnam
I’ve been asked more than a few times this year if it is at all possible to transmit 3D over digital terrestrial television broadcasting (DTTB), or what we know simply as “free digital TV.” There seems to be a perception that one must have a Pay TV subscription service (cable, DBS, FiOS, or U-Verse) to access 3D programming.
Believe it or not, carrying 3D over terrestrial broadcast stations is mostly a business decision. Yes, major TV networks like CBS, NBC, Fox, and ABC could start broadcasting programs in 3D right now. And your 3D-enabled TV would be able to process the 3D signals correctly so the programs can be watched with active-shutter glasses. (I’m not going to discuss color anaglyph 3D here, which works over any TC channel, but produces the lowest quality of 3D.)
The ‘catch’ is that the 3D content would have to be delivered in a frame-compatible format, such as 720p/60 top + bottom (like ESPN uses), or 1080i/30 side-by-side (like DirecTV uses). Both of these formats were specifically developed to fit in a standard 6 MHz channel space, using a maximum bit rate of about 19.39 Mb/s. And in fact, broadcasts of 3D content from earlier this year were delivered in the MPEG2 format that is standard for over-the-air digital TV.
Read the whole story here.