Broadcasting
3D Broadcasting Worldwide Technology
The broadcast signal input interface in television sets is actually settling on side-by-side technologyNote 1) (Fig. 2). Different manufacturers have adopted different approaches to displaying the 3D imagery, such as frame sequential† (FS) or Xpol†, but the input interface is fairly independent of the display technology. Panasonic and Sony say their 3D sets can handle 3D broadcasting and video distribution from BS11, Jupiter Telecommunications Co., Ltd. (J:COM) of Japan and SKY Perfect JSAT Holdings Inc. of Japan. BS11’s Endo adds “We are still verifying interoperability of sets from various manufacturers, but there aren’t any problems so far.”
Note 1) 3D TVs from Panasonic and Sony support side-by-side, High-Definition Multimedia Interface (HDMI) 1.4, and top-and-bottom, which inserts each images for left and right eye at the top and bottom of each frame.
†Frame sequential (FS) method: One method of displaying 3D imagery. The frame of the images for left and right eye are displayed alternately over time, synched to LCD shutter glasses for viewing.
†Xpol method: Another method of displaying 3D imagery. Polarizing film is affixed over the panel, and the polarization direction alternated for each horizontal row of pixels. The left and right images are displayed line-by-line.
Most 3D image broadcasting systems have adopted side-by-side because it ensures frame compatibility† with existing broadcast technology (Fig. 3). In side-by-side, two images for left and right eye captured with the 3D camera are compressed into two frames, and broadcast as a single video frame. The television splits out the left and right images from the received frame, decompresses each to 2x and displays the result.
†Frame compatibility: A video frame using the new broadcasting method is still compatible with existing broadcast video frames, which means that the relay systems will not have to be changed when the broadcasting scheme is.