This article's factual accuracy may be compromised due to out-of-date information.(January 2012) |
DVB 3D-TV is a deprecated [1] standard that partially came out at the end of 2010 which included techniques and procedures to send a three-dimensional video signal through actual DVB transmission standards (cable, terrestrial or satellite). There was a commercial requirement text for 3D TV broadcasters and set-top box manufacturers, but no technical information was in there.
3D television technology was already in its first steps regarding its standardization, the major 3D market was in theaters and Blu-ray Disc players with stereoscopic systems, but in the near future it could be extended to diffusion, and later free viewpoint television will come into our homes, which mean the need of new coding and transmission standards.
The implementation of first generation of DVB 3D-TV could be staggered:
Matrix of signal formats for 3DTV:
Compatibility level | 1st generation 3DTV | 2nd generation 3DTV | 3rd generation 3DTV |
---|---|---|---|
Level 4: | 2D HD + MVC (L, R formed by matrixing: depth info) | 2D HD + MVC (Depth, occlusion and transparency data) | |
Level 3: | Frame compatible + MPEG resolution extension (ex. SVC) | ||
Level 2: | L and R in same HD frame | ||
Level 1: | Color anaglyph |
Regarding how a signal once it's decoded is sent to the display, current stereoscopic systems use a frame-sequential 3D signal. Left and right frames are sent alternately to the display and by diverse systems like shuttered glasses or polarized glasses are then shown to each eye. This involves that the real frame frequency halves the video frame frequency.
In Phase 1 system, only frame-sequential 3D is allowed, using frame compatible (CFC) format. This is made by a spatial multiplex that combines the left and right video sequences in one HD stream which is coded with H.264 as a single image. This allows to handle video as normal HD video using typical channels and interfaces like HDMI, which is possible in this 1.4a version. Frame compatible (CFC) model is also compatible with 2D HD mode in the same channel, adding some signalling for switching from 2D to 3D.
There are basically two ways to do spatial multiplex: Side by side and Top and bottom, but additional spatial multiplex formats have been proposed in order to improve picture quality by providing a better balance between the V and H resolution.
Side by side (SbS) format just put the left and right images one next to the other in an HD image. Because of this, a horizontal decimate is required which causes halving of horizontal definition. DVB 3D-TV supports following SbS formats:
Top and Bottom (TaB) format put left and right images one above the other in a HD image. In this case, vertical decimate is required which causes halving of vertical definition. DVB 3D-TV supports following TaB formats:
There are basically two types of text displayed on screen that need additional broadcasting information to be displayed on a 3D display:
The main function of signaling for frame compatible 3DTV is to signal the presence of a 3D or 2D video stream. It must be also possible to include in the broadcast signal information about the pixel arrangement used to decimate the master HDTV full samples/line pictures to create the anamorphic version, if 3D is available. It's interesting to signal also for 3D receivers the 3D events that are available, for which 3D availability should appear on EPG. For future service compatible (CSC) 3DTV, signal that a 3D version of a 2D service or event is being simulcast, and vice versa will be needed.
Multiview video coding is a compression standard appended from H.264/MPEG-4 AVC which allows send stereoscopic 3D video without resolution loss due to spatial multiplex, and reducing overhead of sending 2 HD images up to 50% and in a single video stream. It is used in Blu-ray players, but at the moment it's not applicable to broadcast because of the processing time for encoding, which uses motion compensation algorithms. Nevertheless, there were some experiments with MVC 3D broadcast by Fraunhofer society [4] over 2nd generation DVB (DVB-T2, DVB-C2 and DVB-S2).
Total Free viewpoint television can be reached by capturing multiple views and extracting 2D+depth information from them to create a 3D model of the scene. This system was being investigated, but the coding complexity and great bandwidth requirements make current broadcasting applications using Multiview Video Coding impractical, so a totally new compression scheme and capture techniques need to be investigated.
Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) systems, which, in turn, were replaced by flat-panel displays of several types.
Digital Video Broadcasting (DVB) is a set of international open standards for digital television. DVB standards are maintained by the DVB Project, an international industry consortium, and are published by a Joint Technical Committee (JTC) of the European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU).
Advanced Video Coding (AVC), also referred to as H.264 or MPEG-4 Part 10, is a video compression standard based on block-oriented, motion-compensated coding. It is by far the most commonly used format for the recording, compression, and distribution of video content, used by 91% of video industry developers as of September 2019. It supports a maximum resolution of 8K UHD.
DVB-T, short for Digital Video Broadcasting – Terrestrial, is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in Singapore in February 1998. This system transmits compressed digital audio, digital video and other data in an MPEG transport stream, using coded orthogonal frequency-division multiplexing modulation. It is also the format widely used worldwide for Electronic News Gathering for transmission of video and audio from a mobile newsgathering vehicle to a central receive point. It is also used in the US by Amateur television operators.
Advanced Television Systems Committee (ATSC) standards are an international set of standards for broadcast and digital television transmission over terrestrial, cable and satellite networks. It is largely a replacement for the analog NTSC standard and, like that standard, is used mostly in the United States, Mexico, Canada, South Korea and Trinidad & Tobago. Several former NTSC users, such as Japan, have not used ATSC during their digital television transition, because they adopted other systems such as ISDB developed by Japan, and DVB developed in Europe, for example.
Serial digital interface (SDI) is a family of digital video interfaces first standardized by SMPTE in 1989. For example, ITU-R BT.656 and SMPTE 259M define digital video interfaces used for broadcast-grade video. A related standard, known as high-definition serial digital interface (HD-SDI), is standardized in SMPTE 292M; this provides a nominal data rate of 1.485 Gbit/s.
HD-MAC was a broadcast television standard proposed by the European Commission in 1986, as part of Eureka 95 project. It belongs to the MAC - Multiplexed Analogue Components standard family. It is an early attempt by the EEC to provide High-definition television (HDTV) in Europe. It is a complex mix of analogue signal, multiplexed with digital sound, and assistance data for decoding (DATV). The video signal was encoded with a modified D2-MAC encoder.
720p is a progressive HD signal format with 720 horizontal lines/1280 columns and an aspect ratio (AR) of 16:9, normally known as widescreen HD (1.78:1). All major HD broadcasting standards include a 720p format, which has a resolution of 1280×720p.
High-definition video is video of higher resolution and quality than standard-definition. While there is no standardized meaning for high-definition, generally any video image with considerably more than 480 vertical scan lines or 576 vertical lines (Europe) is considered high-definition. 480 scan lines is generally the minimum even though the majority of systems greatly exceed that. Images of standard resolution captured at rates faster than normal, by a high-speed camera may be considered high-definition in some contexts. Some television series shot on high-definition video are made to look as if they have been shot on film, a technique which is often known as filmizing.
1080p is a set of HDTV high-definition video modes characterized by 1,920 pixels displayed across the screen horizontally and 1,080 pixels down the screen vertically; the p stands for progressive scan, i.e. non-interlaced. The term usually assumes a widescreen aspect ratio of 16:9, implying a resolution of 2.1 megapixels. It is often marketed as Full HD or FHD, to contrast 1080p with 720p resolution screens. Although 1080p is sometimes referred to as 2K resolution, other sources differentiate between 1080p and (true) 2K resolution.
An active shutter 3D system is a technique of displaying stereoscopic 3D images. It works by only presenting the image intended for the left eye while blocking the right eye's view, then presenting the right-eye image while blocking the left eye, and repeating this so rapidly that the interruptions do not interfere with the perceived fusion of the two images into a single 3D image.
In television technology, Active Format Description (AFD) is a standard set of codes that can be sent in the MPEG video stream or in the baseband SDI video signal that carries information about their aspect ratio and other active picture characteristics. It has been used by television broadcasters to enable both 4:3 and 16:9 television sets to optimally present pictures transmitted in either format. It has also been used by broadcasters to dynamically control how down-conversion equipment formats widescreen 16:9 pictures for 4:3 displays.
DVB-T2 is an abbreviation for "Digital Video Broadcasting – Second Generation Terrestrial"; it is the extension of the television standard DVB-T, issued by the consortium DVB, devised for the broadcast transmission of digital terrestrial television. DVB has been standardized by ETSI.
TDVision Systems, Inc., was a company that designed products and system architectures for stereoscopic video coding, stereoscopic video games, and head mounted displays. The company was founded by Manuel Gutierrez Novelo and Isidoro Pessah in Mexico in 2001 and moved to the United States in 2004.
2D-plus-Depth is a stereoscopic video coding format that is used for 3D displays, such as Philips WOWvx. Philips discontinued work on the WOWvx line in 2009, citing "current market developments". Currently, this Philips technology is used by SeeCubic company, led by former key 3D engineers and scientists of Philips. They offer autostereoscopic 3D displays which use the 2D-plus-Depth format for 3D video input.
High-definition television (HDTV) describes a television or video system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since at least 1933; in more recent times, it refers to the generation following standard-definition television (SDTV). It is the standard video format used in most broadcasts: terrestrial broadcast television, cable television, satellite television.
3D television (3DTV) is television that conveys depth perception to the viewer by employing techniques such as stereoscopic display, multi-view display, 2D-plus-depth, or any other form of 3D display. Most modern 3D television sets use an active shutter 3D system or a polarized 3D system, and some are autostereoscopic without the need of glasses. As of 2017, most 3D TV sets and services are no longer available from manufacturers.
Multi View Video Coding is a stereoscopic video coding standard for video compression that allows for encoding video sequences captured simultaneously from multiple camera angles in a single video stream. It uses the 2D plus Delta method and it is an amendment to the H.264 video compression standard, developed jointly by MPEG and VCEG, with the contributions from a number of companies, such as Panasonic and LG Electronics.
2D Plus Delta is a method of encoding a 3D image and is listed as a part of MPEG2 and MPEG4 standards, specifically on the H.264 implementation of the Multiview Video Coding extension. This technology originally started as a proprietary method for Stereoscopic Video Coding and content deployment that utilizes the left or right channel as the 2D version and the optimized difference or disparity (Delta) between that image channel view and a second eye image view is injected into the video stream as user data, secondary stream, independent stream, enhancement layer or NALu for deployment. The Delta data can be either a spatial stereo disparity, temporal predictive, bidirectional, or optimized motion compensation.
SENSIO Technologies, Inc., also known as SENSIO, was a Montreal company that developed and marketed stereoscopic image-processing technologies facilitating the creation and delivery of 3D content. To promote widespread 3D adoption, SENSIO was active on several fronts: aggregating and distributing 3D content in its SENSIO® Hi-Fi 3D format; supplying the technology to enable high-fidelity, quality-enhanced 3D images delivered over the existing 2D infrastructure; developing technologies that eased user interaction with 3D content; and ensuring compatibility by conforming to existing constraints and promoting standardization.