Terrestrial broadcasting perspective on HDTV delivery

Sarnoff Corporation (formally the David Samoff Research Center) is leading a joint venture consisting of Comark, NBC, IBM, MCI , Sun Microsystems, Thomson, Philips and Advanced Modular Solutions to develop a high definition compressed digital studio. This paper provides an overview of the NIST High Definition Television (HDTV) Broadcast Technology joint venture.

IF A NEW high-tech television is in your future, you might want to bone up on your geometry. Let me explain. In the early days of television, the National Television Standards Commission (NTSC) set the aspect ratio (width divided by height) of the television screen at 4 by 3 or 1.33. Today, you can still buy 4-by-3 sets, or you can buy a widescreen set with an aspect ratio of 16 by 9 or 1.78. Most television stations or channels still broadcast in a 4-by-3 format, so a television set with that aspect ratio makes sense. However, if you watch a lot of movies or programs on high-definition, cable, or satellite channels, a number of these will be widescreen productions. Now here is the downside of this geometry. If you watch a 16-by-9 program on a 4-by-3 set, the screen is boxed--meaning it has black bars on the top and bottom of the screen (Figure 1, top). If you watch a 4-by-3 program on a 16-by-9 set, the image is boxed--meaning there are black bars on the left and right of the screen (Figure 1, bottom). In either case, a sizable portion of the television screen is unused. (I should mention here that Europe and other parts of the world do not use the NTSC standard, so some of what follows does not apply to readers outside the U.S.) [FIGURE 1 OMITTED] There are several work arounds for letter boxing and pillar boxing. Most widescreen sets (16 by 9) have aspect adjustments. The most common aspect adjustment is to stretch--or widen--a 4-by-3 program to fill the widescreen. I suppose you could get used to this, but it sure makes people look plump. Going in the opposite direction, some widescreen DVD movies are also available in full-screen versions, but this is becoming less and less common. A second downside to this geometry quandary is that watching a 4-by-3 program on a large widescreen set (unstretched) is like watching it on a significantly smaller 4-by-3 set. What you thought was going to look like a large picture looks a lot smaller. Here's a brief tabular presentation of effective viewing reduction for widescreen sets of various sizes. (The figures are for diagonal measurements and are in inches.) CNet has an online calculator that will give you these comparisons for any size widescreen set at http://reviews.cnet.com/ 4520-7608_7-1016109-4.html. Hint: CNet calls pillar boxing window boxing, and remember to use the lower of the two calculators. The bottom line is you must examine your viewing habits before you buy a new television. Of course, if you have the space, you can have a television room and a separate home theater room for your widescreen. Ultimately, most people will buy a newer widescreen set because they want to move up to High-Definition Television (HDTV) and because they like the movie theater look of the newer format. The old television standard set by the NTSC was labeled 480i. This format had 480 horizontal lines of resolution that were, as the i signifies, That is, the television displayed the odd-numbered lines every 60th of a second and the even-numbered lines in the next 60th of a second. You can actually see these lines if you look closely at the screen. Unfortunately, viewers rarely saw a television program with all 480 lines of resolution, since most programming was produced with only about 250 lines of resolution. And interlacing causes an imperceptible flicker that can contribute to eyestrain. The most common HDTV standards are 720p and 1080i or 1080p. Each has as many lines of resolution as the numbers suggest. The p stands for progressive scan, which means that all lines are displayed at one time--not interlaced. Suffice it to say, if you buy an HDTV you should be sure it can display at least one of the standards mentioned here. Another important consideration is the number of pixels (picture elements) an HDTV can display. Most newer HDTVs have pixel ratings of about 1280 by 720. …

Efficient error protection strategies for robust satellite broadcast of high-definition television (HDTV) and conventional TV are investigated. The concatenated Reed-Solomon/convolutional code is preferred over the RS code for fewer adverse effects on variable-length codes. A decoded bit error rate of 10/sup -10/ or below can be achieved for all transmitted information at a low threshold E/sub b//N/sub 0/. The most critical video packet data are received near-error-free by using an additional layer of block coding with minimal redundancy and complexity. The effect of loss of synchronization for variable-length codewords due to channel errors is minimized by simple error detection and concealment methods. Digital transmission architectures for the satellite broadcast of HDTV and conventional TV are outlined. >

HDTV and DRM: A Need of Further Regulation?

Terrestrial broadcast television in the United States has remained essentially unchanged in the last fifty years except for the addition of color and stereo sound. Today, personal computers are addressing the need for random access of high resolution images and CD quality audio. Furthermore, advances in digital video compression and digital communication technology have cleared the way toward offering high resolution video and audio services to consumers using traditional analog communications channels. In 1987, the U.S. Federal Communications Commission (FCC) chartered an advisory committee to recommend an advanced television system for the United States. From 1990 to 1992, the Advanced Television Test Center (ATTC) tested four all-digital systems, one analog High Definition Television (HDTV) system, and one enhancement NTSC system using broadcast and cable television environment simulators. The formation of the HDTV Grand Alliance in May of 1993 resulted from the withdrawal of the only analog HDTV system from the competition and a stalemate between the other four all-digital systems. The HDTV Grand Alliance system is composed of the best components from previously competing digital systems demonstrated to the FCC. Moving Pictures Experts Group (MPEG-2) syntax is used with novel encoding techniques to deliver a set of video scanning formats for a variety of applications. This paper describes the important features and concepts embodied in the HDTV Grand Alliance system.

High performance audio and video codecs and ever increasing bandwidths of data communications networks have enabled multi-platform delivery of high definition media content via transmission channels such as terrestrial broadcast, broadband IP networks and mobile telecommunications systems. Media content consumption becomes ubiquitous and more personalized than ever before and audio is often rendered through headphones. Attentions should be paid to sound quality, and therefore high definition virtual auditory space (VAS) is sought after as an ideal solution. Stereophonic and surround sound are still commonplace while spatial audio is in its infancy to meet the demand of 2.5/3 D high definition video. Binaural headphone rendering offers ultimate spatial audio and source localization; however, individual head-related transfer functions (HRTFs), head movement tracking and suitably synthesized signals are needed to achieve its full potential. Most audio recordings to date are intended and hence best for loudspeaker rendering. Good cross-feed filters can be an interim solution to improve headphone user experience. This paper proposes a universal cross-feed filter. HRTFs at specific source locations were first considered to derive the cross-feed filters. User preferred HRTF parameters were also identified with a variety of representative soundtracks. The transfer functions were measured and simplified to derive user preferred universal cross-feed filters for all. Validation tests confirmed improved listening experience.

An introduction is given to papers submitted to a November 1991 meeting of the International Radio Consultative Committee (CCIR) Task Group on high-definition television (HDTV). The purpose of the digital HDTV broadcasting documents is to respond to questions posed in the CCIR. Key issues are harmonization of high resolution imaging standards among applications, compression algorithms, source coding, channel coding, modulation techniques, and spectrum strategy. Since the information provided to the CCIR did not contain block diagrams of the proposed systems, block diagrams of a typical encoder and decoder are provided. The diagrams are not precisely descriptive of any of the proposed systems, but are generally descriptive of all of them. >

A high‐definition television (HDTV) video compression encoder is being constructed for use during the standardization process for United States terrestrial broadcast HDTV. The encoder generates an MPEG‐2 main profile/high level compliant bitstream at compressed data rates from 10–80 million bits/second. Both interlaced and progressive image formats in image sizes up to 1080 lines × 1920 pixels per line are supported.©1994 John Wiley & Sons Inc

The mitigation of random effects in a wireless communication channel is a problem considered for many years. In the present day context, given the ever increasing need for, and growth of, bandwidth intensive applications like streaming wireless HD video on fast moving user equipment (UEs, i.e., user communication devices), this issue has intensified from being a theoretical pursuit to a must-be-solved practical endeavor. In that regard, the ability to accurately model the outdoor (or indoor) propagation conditions in a laboratory setting becomes vital to validating state-of-the-art wireless standards and the devices that derive from them. Laboratory-based analysis is a significant catalyst in reducing the time-to-market for telecom equipment manufacturers. Modeling a wireless channel has been a topic under quite a bit of study. This has progressed from the Jakes model developed for single antenna systems to the correlation and ray-based models used for multiple antenna systems. The models prescribed by the 3rd Generation Partnership Project (3GPP) in its standards, like the ray-based model, aim to realistically reproduce channel environments in software and hardware, by incorporating all the variables that characterize any particular fading scenario. In this thesis, the technical report produced by 3GPP detailing the Spatial Channel Modeling (SCM) for multiple input multiple output (MIMO) simulations is followed closely as a basis for developing a real-time channel emulator on a National Instruments (NI) based Real Time (RT) Platform. First, a general purpose channel emulator is described in terms of its structure and functionality and currently known channel models are briefly investigated. Next, the spatial channel model in the standard is described in detail along with the reasons for choosing to use it in the thesis. All the parameters involved are defined, and the formula for constructing the channel is carefully investigated. Next, the channel emulator built on the National Instruments LabVIEW platform is described along with both the changes and modifications made to the design parameters so as to adapt it to the operating constraints of the RT platform. The spatial and temporal characteristics of the model are also described and plotted. Finally, the model is tested for reliability by methodically changing the various channel parameters and observing their effects on an Orthogonal Frequency Division Multiplexing (OFDM) test vector by generating BER performance plots in MATLAB. Diversity schemes are also employed to improve rate performance.

Multiresolution, or scalable, video coding has emerged to be of great interest in the compression community. It has been recognized that many applications, such as, image database browsing, desktop computing, terrestrial broadcasting, and others, can benefit from multiresolution viewing of embedded data sets. In this paper we present a new three-dimensional subband coder which provides six different spatio-temporal resolutions of a video signal. Motion-compensated temporal filtering (MCTF) is used for temporal analysis. The encoding algorithm efficiently compresses the data from the six resolutions into a single bit-stream while removing data which is redundant across different resolutions. Our algorithm successfully merges spatial and temporal scalability without imposing restrictions on which of the six video resolutions can be decoded, while allowing optimal encoding of the video at each spatial and temporal resolution.

This paper presents the results of a field research about the level of knowledge and familiarity of journalists of Vojvodina's newspapers and radio stations regarding the digitalization of TV production and broadcasting. According to the 'Regulations on the transition from analogue to digital broadcasting of television programs and access to the multiplex in terrestrial digital broadcasting' (2011) the promotion of this process in public is an important element for its success. A key aspect of this is that not only reporters from state controlled television stations should have basic knowledge of, and interest in, this topic, but that other journalists (from local and regional newspapers and radio stations) do as well. Their public advocacy and preparation of citizens in local communities for the day when the television signal will fully switch to digital terrestrial broadcasting is very important. Initial digital broadcasting in Serbia began in March, 2012. The study shows that journalists of those media outlets are not empowered to take on the task set ahead of them.

Advanced digital high definition television (AD-HDTV) is an all-digital simulcast system designed to provide high-quality HDTV service to a large coverage area through a single 6 MHz terrestrial broadcast 'taboo' channel. The paper describes the technical details of the AD-HDTV video coding system and provides an analysis of the system performance.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

This article analyses low-density parity-check (LDPC) codes for forward error correction (FEC) in the next generation of digital terrestrial broadcasting systems for transmitting high-volume content services, such as ultra high definition television (UHDTV). We assess the performance of the LDPC codes used by the Advanced ISDB-T system with 2x2 MIMO transmission using experimental data obtained in field measurements in Brazil. Channel power, carrier-to-noise threshold, and receiving threshold were measured for four different low-rates LDPC codes, two modulation types, and three receiving antenna heights at outdoor sites in urban areas. The coverage analysis shows that the channel power presents a similar distribution for horizontal and vertical polarized signals. C/N threshold analysis shows that in sites with high vehicular traffic, the C/N threshold and reception threshold values were much higher than in other sites with less heavy vehicular traffic. Among the five coding-modulation combinations used in the field tests, the transmission configuration with LDPC code rate 2/16 and QPSK modulation was the one that presented the best results partially meeting the requirement of C/N≤0dB. The transmission configuration with LDPC code rate 3/16 and QPSK modulation showed C/N results just above 0dB, but offering 50% higher data transmission rate.

With the increasing demand for efficient video delivery over terrestrial broadcasting systems, selecting the appropriate video compression standard is crucial for optimizing bandwidth usage and maintaining high-quality transmissions. This study presents a comparative analysis of MPEG-4 (H.264/AVC) and HEVC (H.265) video compression standards in the context of Digital Video Broadcasting - Second Generation Terrestrial (DVB-T2) transmission. MPEG-4 has been widely adopted in previous broadcasting systems, while HEVC offers improved compression efficiency, making it a promising alternative for modern broadcasting applications. The research evaluates both codecs based on key performance metrics including compression ratio, video quality (measured via PSNR and SSIM), bitrate efficiency, and computational complexity. Test scenarios are developed using standard-definition and high-definition video content, encoded under similar transmission parameters suitable for DVB-T2. The results demonstrate that HEVC achieves up to 50% bitrate savings compared to MPEG-4 for equivalent video quality, thereby allowing more channels or higher quality content within the same bandwidth. However, HEVC's increased encoding complexity and hardware requirements are noted as potential limitations for deployment in existing infrastructure. This analysis provides critical insights into the trade-offs between legacy and next-generation codecs for DVB-T2 broadcasting, supporting broadcasters and policymakers in making informed decisions regarding system upgrades and spectrum management.