It should be noted that 3D film and 3DTV trials have a long history, as shown in Fig. 1.7 (based partially on Ref. 2). However, the technology has finally
progressed enough at this juncture, for example with the deployment of digital television (DTV) and High Definition Television (HDTV), that regular commercial services will finally be introduced at this juncture.
We start by noting that there are two general commercial-grade display approaches for 3DTV: (i) stereoscopic TV, which requires special glasses to watch 3D movies, and (ii) autostereoscopic TV, which displays 3D images in such a manner that the user can enjoy the viewing experience without special accessories.
Short-term commercial 3DTV deployment, and the focus of this book, is on stereoscopic 3D imaging and movie technology. The stereoscopic approach follows the cinematic model, is simpler to implement, can be deployed more
quickly (including the use of relatively simpler displays), can produce the best results in the short term, and may be cheaper in the immediate future. However, the limitations are the requisite use of accessories (glasses), somewhat limited positions of view, and physiological and/or optical limitations including possible eye strain. In summary, (i) glasses may be cumbersome and expensive (especially for a large family) and (ii) without the glasses, the 3D content is unusable.
Autostereoscopic 3DTV eliminates the use of any special accessories: it implies that the perception of 3D is in some manner automatic, and does not require devices—either filter-based glasses or shutter-based glasses. Autostereoscopic displays use additional optical elements aligned on the surface of the screen, to ensure that the observer sees different images with each eye. From a home screen hardware perspective the autostereoscopic approach is more challenging, including the need to develop relatively more complex displays; also, more complex acquisition/coding algorithms may be needed to make optimal use of the technology. It follows that this approach is more complex to implement, will require longer to be deployed, and may be more expensive in the immediate future. However, this approach can produce the best results in the long term, including accessories-free viewing, multi-view operation allowing both movement and different perspective at different viewing positions, and better physiological and/or optical response to 3D.
Table 1.1 depicts a larger set of possible 3DTV (display) systems than what we identified above. The expectation is that 3DTV based on stereoscopy will experience earlier deployment compared with other technological alternatives.
Hence, this text focuses principally on stereoscopy. Holography and integral imaging are relatively newer technologies in the 3DTV context compared to stereoscopy; holographic and/or integral imaging 3DTV may be feasible late in
the decade. There are a number of techniques to allow each eye to view the separate pictures, as summarized in Table 1.2 (based partially on Ref. 3.) All of these techniques work in some manner, but all have some shortcomings.
To highlight the commercial interest in 3DTV at press time, note that ESPN announced in January 2010 that it planned to launch what would be the world’s
first 3D sports network with the 2010 World Cup soccer tournament in June 2010, followed by an estimated 85 live sports events during its first year of operation. DIRECTV announced that they will start 3D programming in 2010. DIRECTV’s new HD 3D channels will deliver movies, sports, and entertainment content from some of the world’s most renowned 3D producers. DIRECTV is currently working with AEG/AEG Digital Media, CBS, Fox Sports/FSN, Golden Boy
Promotions, HDNet, MTV, NBC Universal, and Turner Broadcasting System, Inc., to develop additional 3D programming that will debut in 2010–2011. At launch, the new DIRECTV HD 3D programming platform will offer a 24/7 3D pay per view channel focused on movies, documentaries, and other programming;
a 24/7 3D DIRECTV on Demand channel; and a free 3D sampler demo channel featuring event programming such as sports, music, and other content. Comcast has announced that its VOD (Video-On-Demand) service is offering a number
of movies in anaglyph 3D (as well as HD) form. Comcast customers can pick up 3D anaglyph glasses at Comcast payment centers and malls “while supplies last” (anaglyph is a basic and inexpensive method of 3D transmission that relies on inexpensive colored glasses, but its drawback is the relatively low quality.) Verizon’s FiOS was expected to support 3DTV programming by Late 2010. Sky TV in the United Kingdom was planning to start broadcasting programs in 3D in the fall of 2010 on a dedicated channel that will be available to anyone who has the Sky HD package; there are currently 1.6 million customers who have a Sky HD set-top box. Sky TV has not announced what programs will be broadcast in 3D, but it is expected to broadcast live the main Sunday afternoon soccer game from the Premiership in 3D from the 2011 season, along with some arts documentaries and performances of ballet . Sky TV has already invested in installing special twin-lens 3D cameras at stadiums.
3DTV television displays could be purchased in the United States and United Kingdom as of the spring of 2010 for $1000–5000 initially, depending on technology and approach. Liquid Crystal Display (LCD) systems with active
glasses tend to generally cost less. LG released its 3D model, a 47-in. LCD screen, expected to cost about $3000; with this system, viewers will need to wear polarized dark glasses to experience broadcasts in 3D. Samsung and Sony also announced they were bringing their own versions to market by the summer of 2010, along with 3D Blu-ray players, allowing consumers to enjoy 3D movies such as Avatar and Up, in their own homes . Samsung and Sony’s models
use LED (Light-Emitting Diode) screens which are considered to give a crisper picture and are, therefore, expected to retail for about $5000 or possibly more. While LG is adopting the use of inexpensive polarizing dark glasses, Sony and Samsung are using active shutter technology. This requires users to buy expensive dark glasses, which usually cost more than $50 and are heavier than the $2–3 plastic polarizing ones. Active shutter glasses alternately darken over one eye, and then the other, in synchronization with the refresh rate of the screen using shutters built into the glasses (using infrared or Bluetooth connections). Panasonic Corporation has developed a full HD 3D home theater system consisting of a plasma full HD 3D TVs, 3D Blu-ray player, and active shutter 3D glasses. The 3D display was originally available in 50-in., 54-in., 58-in. and 65-in. class sizes. High-end systems are also being introduced; for example Panasonic announced a 152-in. 4K × 2K (4096 × 2160 pixels)-definition full HD 3D plasma display. The display features a new Plasma Display Panel (PDP) that uses self-illuminating technology. Self-illuminating plasma panels offer excellent response to moving images with full motion picture resolution, making them suitable for rapid 3D image display (its illuminating speed is about one-fourth the speed of conventional full HD panels). Each display approach
has advantages and disadvantages as shown in Table 1.3.
It is to be expected that 3DTV for home use is likely to first see penetration via stored media delivery. For content source, proponents make the case that BD “is the ideal platform” for the initial penetration of 3D technology in the mainstream market because of the high quality of pictures and sound it offers film producers. Many products are being introduced by manufacturers: for example at the 2010 Consumer Electronics Show (CES) International Trade Show, vendors introduced eight home theater product bundles (one with 3D capability), 14 new players (four with 3D capability), three portable players, and a number of software titles. In 2010 the Blu-ray Disc Association (BDA) launched a new 3D Blu-ray logo to help consumers quickly discern 3D-capable Blu-ray players from 2D-only versions (Fig. 1.8) .
The BDA makes note of the strong adoption rate of the Blu-ray format. In 2009, the number of Blu-ray households increased by more than 75% over 2008 totals. After four years in the market, total Blu-ray playback devices (including
both set-top players and PlayStation3 consoles) numbered 17.6 million units, and 16.2 million US homes had one or more Blu-ray playback devices. By comparison, DVD playback devices (set-tops and PlayStation2 consoles) reached
14.1 million units after four years, with 13.7 million US households having one or more playback devices. The strong performance of the BD format is due to a number of factors, including the rapid rate at which prices declined due to
competitive pressures and the economy; the rapid adoption pace of HDTV sets, which has generated a US DTV household penetration rate exceeding 50%; and, a superior picture and sound experience compared to standard definition and even
other HD sources. Another factor in the successful adoption pace has been the willingness of movie studios to discount popular BD titles . Blu-ray software unit sales in 2009 reached 48 million, compared with 22.5 million in 2008, up
by 113.4%. A number of movie classics were available at press time through leading retailers at sale prices as low as $10.
The BDA also announced (at the end of 2009) the finalization and release of the Blu-ray 3D specification. These BD specifications for 3D allow for full HD 1080p resolution to each eye. The specifications are display agnostic, meaning
they apply equally to plasma, LCD, projector, and other display formats regardless of the 3D systems those devices use to present 3D to viewers. The specifications also allow the PlayStation3 gaming console to play back 3D content.
The specifications that represent the work of the leading Hollywood studios and consumer electronic and computer manufacturers, will enable the home entertainment industry to bring stereoscopic 3D experience into consumers’ living
rooms on BD, but will require consumers to acquire new players, HDTVs, and shutter glasses. The specifications allow studios (but do not require them) to package 3D Blu-ray titles with 2D versions of the same content on the same disc. The specifications also support playback of 2D discs in forthcoming 3D players and can enable 2D playback of Blu-ray 3D discs on an installed base of BD. The Blu-ray 3D specification encodes 3D video using the Multi-View Video Coding (MVC) codec, an extension to the ITU-T H.264 Advanced Video Coding (AVC) codec currently supported by all BD players. MPEG-4 (Moving Picture Experts Group 4)-MVC compresses both left and right eye views with a typical 50% overhead compared to equivalent 2D content, according to BDA and can provide full 1080p resolution backward compatibility with current 2D BD players .
The broadcast commercial delivery of 3DTV on a large scale—whether over satellite/Direct-To-Home (DTH), over the air, over cable systems, or via IPTV—may take some number of years because of the relatively large-scale infrastructure that has to be put in place by the service providers and the limited availability of 3D-ready TV sets in the home (implying a small subscriber, and so small revenue base). A handful of providers were active at press time, as described earlier, but general deployment by multiple providers serving a geographic market will come at a future time. Delivery of downloadable 3DTV files over the Internet may occur at any point in the immediate future, but the provision of a broadcast-quality service over the Internet is not likely for the foreseeable future.
At the transport level, 3DTV will require more bandwidth of regular programming, perhaps even twice the bandwidth in some implementations (e.g., simulcasting—the transmission of two fully independent channels4); some newer schemes such as “video + depth” may require only 25% more bandwidth compared to 2D, but these schemes are not the leading candidate technologies for actual deployment in the next 2–3 years. Other interleaving approaches use the same bandwidth of a channel now in use, but at a compromise in resolution. Therefore, in principle, if HDTV programming is broadcast at high quality, say, 12–15Mbps using MPEG-4 encoding, 3DTV using the simplest methods of two independent streams will require 24–30Mbps.5 This data rate does not fit a standard over-the-air digital TV (DTV) channel of 19.2 Mbps, and will also be a challenge for non-Fiber-To-The-Home (non-FTTH) broadband Internet connections. However, one expects to see the emergence of bandwidth reduction techniques, as alluded to above. On the other hand, DTH satellite providers, terrestrial fiberoptic providers, and some cable TV firms should have adequate bandwidth to support the service. For example, the use of the Digital Video Broadcast Satellite Second Generation (DVB-S2) allows a transponder to carry 75 Mbps of content with modulation using an 8-point constellation and twice that much with a 16-point constellation. The trade-off would be, however (if we use the raw HD bandwidth just described as a point of reference), that a DVB-S2 transponder that would otherwise carry 25 channels of standard definition video or 6–8 channels of HD video would now only carry 2–3 3DTV channels. To be pragmatic about this issue, most 3DTV providers are not contemplating delivering full resolution as just described and/or the transmission of two fully independent channels (simulcasting), but some compromise; for example, lowering the per eye data rate such that a 3DTV program fits into a commercial-grade HDTV channel (say 8–10 Mbps), using time interleaving or spatial compression—again, this is doable but comes with the degradation of ultimate resolution quality.
There are a number of alternative transport architectures for 3DTV signals, also depending on the underlying media. As noted, the service can be supported by traditional broadcast structures including the DVB architecture, wireless 3G/4G transmission such as DVB-H approaches, Internet Protocol (IP) in support of an IPTV-based service (in which case it also makes sense to consider IPv6) and the IP architecture for internet-based delivery (both non–real time and streaming). The specific approach used by each of these transport methods will also depend on the video-capture approach. One should note that in the United States, one has a well-developed cable infrastructure in all Tier 1 and Tier 2 metropolitan and suburban areas; in Europe/Asia, this is less so, with more DTH delivery (in the United States DTH tends to serve more exurban and rural areas). A 3DTV rollout must take these differences into account and/or accommodate
both. In reference to possible cable TV delivery, CableLabs announced at press time that it started to provide testing capabilities for 3D TV implementation scenarios over cable; these testing capabilities cover a full range of technologies
including various frame-compatible, spatial multiplexing solutions for transmission .
Standards are critical to achieving interworking and are of great value to both consumers and service providers. The MPEG of the International Organization for Standardization/International Electrotechnical Commission (ISO/IEC) has been working on coding formats for 3D video (and has already completed some of them.) The Society of Motion Picture and Television Engineers (SMPTE) 3D Home Entertainment Task Force has been working on mastering standards. The
Rapporteur Group on 3DTV of the International Telecommunications Union- Radiocommunications Sector (ITU-R) Study Group 6, and the TM-3D-SM group of DVB were working on transport standards.