Society of Motion Picture and Television Engineers (SMPTE) 3D Home Entertainment Task Force

0
119

There is a need for a single mastering standard for viewing stereo 3D content on TVs, PCs, and mobile phones, where the content could originate from optical disks, broadcast networks, or the Internet. To that end, SMPTE formed a 3D Home Entertainment Task Force in 2008 to work the issue and a standards effort was launched in 2009 via an SMPTE 3D Standards Working Group to define a content format for stereo 3D. The SMPTE 3D Standards Working Group had about 200 participants at press time; the Home Master standard was expected to become available in mid-2010. The group is in favor of a mastering standard for the Home Master specification based on 1920 × 1080 pixel resolution at 60 fps/eye. The specification is expected to support an option for falling back to a 2D image. The standard is also expected to support hybrid products, such as BDs that can support either 2D or stereo 3D displays.

SMPTE’s 3D Home Master defines high-level image formatting requirements that impact 3DTV designs, but the larger bulk of the 3DTV standards for hardware are expected to come from other organizations, such as CEA. Studios or game publishers would deliver the master as source material for uses ranging from DVD and BD players to terrestrial and satellite broadcasts and Internet downloadable or streaming files

As we have seen throughout this text, 3DTV systems must support multiple delivery channels, multiple coding techniques, and multiple display technologies. Digital cinema, for example, is addressed with a relatively simple left–right sequence approach; residential TV displays involve a greater variety of technologies necessitating more complex encoding. Content transmission and delivery is also supported by a variety of physical media such as BDs as well as broadcasting, satellite, and cable delivery. The SMPTE 3D Group has been considering what kind of compression should be supported. One of the key goals of the standardization process is defining and/or identifying schemes that minimize the total bandwidth required to support the service; the MVC extension to MPEG- 4/H.264 discussed earlier is being considered by the group. Preliminary studies have shown, however, that relatively little bandwidth may be saved when compared to simulcast because high-quality images require 75–100% overhead and images of medium quality require 65–98% overhead. In addition to defining the representation and encoding standards (which clearly drive the amount of channel bandwidth for the additional image stream), 3DTV service entails other requirements; for example, there is the issue of graphics overlay, captions and subtitles, and metadata. 3D programming guides have to be rethought, according to industry observers; the goal is to avoid floating the guide in front of the action and instead, to push the guide behind the screen and let the action play over it because practical research shows that people found it jarring when the programming guide is brought to the forefront of 3DV images [13]. The SMPTE Group is also looking at format wrappers, such as Material eXchange Format (MXF; a container format for professional digital video and audio media defined by a set of SMPTE standards), whether an electrical interface should be specified, and if depth representation is needed for an early version of the 3DTV service, among other factors [14]. As we have noted earlier in the text, 3DTV has the added consideration of physiological effects because disjoint stereoscopic images can adversely impact the viewer.