Alan P. Cavallerano

The US HDTV standard

This standard for digital high-definition television has been submitted to the Federal Communications Commission for its approval. Based as it is on the MPEG-2 video compression and transport protocol, multiple transmission formats, Dolby AC-3 digital audio, and vestigial sideband digital modulation, this HDTV system will supply the home with superb images and spectacular sound while also, as part of the National Information Infrastructure (NII), relaying digital data. An HDTV system employing multiple transmission formats, digital compression, packetization, and modulation techniques is a marked advance over current world television standards such as NTSC, PAL, or SECAM. >

Decomposition and Recombination of a Wide Aspect Radio Image for ENTSC Two-Channel Television

A video system providing enhanced viewing of television pictures sourced from a widescreen format (e.g. 5¿:3 aspect ratio) should not preclude compatibility with NTSC standards. A plausible scenario

System and technological details of terrestrial/cable NTSC compatible HDTV

Efficient baseband analog processing proven in hardware for a 525-line progressively scanned HDTV (high-definition TV) image is described. The processing steps are also suitable for 1050-line interlaced HDTV images. Specific terrestrial and cable HDTV packaging formats for baseband processing are presented which exploit efficient NTSC (National Television System Committee) compatibility for program delivery in North America. Analog augmentation formats requiring 4 MHz or 3 MHz of spectrum in addition to the NTSC signal are disclosed that may be suitable for taboo channel utilization. All signal components are readily transcodable from a MAC (multiplexed analog component) satellite format utilizing the same generic baseband analog processing method. Augmentation implementation issues associated with an actual hardware prototype are discussed. >

Baseband video processing and the transmission of HDTV signals

The authors address the key concerns in the formulation of new HDTV (high-definition television) systems. The starting point is the derivation of basic definitions of resolution parameters of television systems. Having established the means of representing the static and dynamic resolution of a television system, the authors discuss baseband encoding and decoding methods in terms of spatial and temporal filtering of source images as a means of efficient bandwidth reduction. A method for delivery of HDTV via satellite is detailed, and a simulcast technique for transmission HDTV in a terrestrial environment is presented. The sampling, filtering, subsampling, and transmission packaging provides a high-definition system for the North American HDS/NA. Interference issues are of primary concern when utilizing a taboo channel for terrestrial broadcast, and techniques for minimizing their effects, exploited in HDS/NA, are discussed. >

Grand alliance MPEG‐2‐based video decoder with parallel processing architecture

A practical and unique hardware architecture for video bitstream source decoding and video postprocessing of a Moving Pictures Expert Group (MPEG‐2)‐based high‐definition television (HDTV) compressed bitstream has been implemented to impose minimal limitations on the video source coding algorithm. The Grand Alliance (GA) MPEG‐2‐based HDTV codec achieves a high degree of source and channel coding efficiency while preserving the delivery of high‐resoultion picture quality in a variety of video input and output formats in bandwidth‐limited channels. The video source decoder hardware architecture necessary to achieve the data decoding and ensuing video postprocessing poses numerous technologic challenges to the system designer, who must tradeoff minimizing codec constraints with the eventual commercialization of a video decoder for a consumer television receiver product. The powerful and flexible coding algorithm necessary to satisfy the HDTV picture quality and transmission channel bandwidth limitation requirements results in an encoder‐output bitstream that necessitates high throughout decoding. Although the transmitted bitstream is of constant rate due to rate buffering, bistreams internal to the codec are both peaky and bursty. An intelligent distributive parallel processing decoding architecture has been developed to dynamically partition the MPEG‐2 bitstream into a number of decodable subset bitstreams, while placing minimal constraints on the encoding algorithm. This architecture allows for high‐speed, efficient decoding of the bitstream, and can be a prelude to the development of a cost‐effective consumer product. Further architecture refinements can be explored, including implementation in VLSI.

HDS/NA-6: an analog simulcast high definition television system

A high-definition system for North America (HDS/NA) embracing the simulcast mode of transmission for amplitude-modulated terrestrial and cable environments is described. The AM RF packaging techniques and the pertinent concerns for future tailoring of the system format for taboo channel utilization for broadcast-compatible terrestrial HDTV delivery in 6 MHz are highlighted. Without the constraint of direct NTSC compatibility with this system, carriers may be suppressed and standard NTSC sync headroom may be eliminated. Due to time expansion of all video components, there is a built-in advantage in multipath/echo performance, particularly beneficial for the cable short-echo scenario. The system is naturally expandable to permit an increase in resolution in the presence of additional channel bandwidth. This simulcast format is linked to a linear analog subband subsampling scheme used as a cornerstone for all HDS/NA analog transmission systems, including satellite (FSS and DBS) and augmentation terrestrial and cable formats. The generic HDS/NA subsampling scheme and the packaging of the components for a 6-MHz AM environment are described. >