Scalable video multicast is a new wireless multicast technology. In scalable video multicast, the video program subscribers can view the program in accordance with their link conditions. The scalable video multicast has been employed by many standards, such as MBMS, MBS, and DVB-H.
Traditional mobile networks were initially designed for unicast services, and may waste radio network resources by transmitting the same content in multiple copies to different users. With video multicasting, more efficient resource utilization would however be possible. Multicast service is therefore, a significant part of the current mobile services. Examples include the Multicast/Broadcast Service (MBS) over the WiMAX, the Multimedia Broadcast/Multicast Service (MBMS) within the LTE, the Digital Video Broadcasting services (e.g., DVB-T, DVB-H) defined in European Telecommunication Standard (ETS), and the MediaFLO presented by Qualcomm.
In mobile networks, all frames with multicast Receiver Address are transmitted at one of the rates included in a basic rate set. In order to guarantee coverage to all associated users, the transmission rate is typically fixed to one of the low basic rates. This limits the rate at which multicast data can be sent, for example, high-definition video is hard to send via multicast. To address this problem, scalable video multicasting (SVM) technology has been proposed. In SVM, video is encoded into one base layer (BL) and several enhancement layers (ELs) by using Scalable Video Coding (SVC) technique. The BL ensures the basic video quality of all users and each additional EL further enhances the quality of the video.
A codec is a device or computer program which encodes or decodes a data stream or signal. Codec is a portmanteau of coder/decoder.
In information technology, lossy compression or irreversible compression is the class of data encoding methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size for storing, handling, and transmitting content. The different versions of the photo of the cat on this page show how higher degrees of approximation create coarser images as more details are removed. This is opposed to lossless data compression which does not degrade the data. The amount of data reduction possible using lossy compression is much higher than using lossless techniques.
In computer networking, multicast is group communication where data transmission is addressed to a group of destination computers simultaneously. Multicast can be one-to-many or many-to-many distribution. Multicast should not be confused with physical layer point-to-multipoint communication.
MPEG-1 Audio Layer II or MPEG-2 Audio Layer II is a lossy audio compression format defined by ISO/IEC 11172-3 alongside MPEG-1 Audio Layer I and MPEG-1 Audio Layer III (MP3). While MP3 is much more popular for PC and Internet applications, MP2 remains a dominant standard for audio broadcasting.
Advanced Audio Coding (AAC) is an audio coding standard for lossy digital audio compression. Designed to be the successor of the MP3 format, AAC generally achieves higher sound quality than MP3 at the same bit rate.
Advanced Video Coding (AVC), also referred to as H.264 or MPEG-4 Part 10, Advanced Video Coding, is a video compression standard based on block-oriented, motion-compensated integer-DCT 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 resolutions up to and including 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.
DVB-C stands for "Digital Video Broadcasting - Cable" and it is the DVB European consortium standard for the broadcast transmission of digital television over cable. This system transmits an MPEG-2 or MPEG-4 family digital audio/digital video stream, using a QAM modulation with channel coding. The standard was first published by the ETSI in 1994, and subsequently became the most widely used transmission system for digital cable television in Europe, Asia and South America. It is deployed worldwide in systems ranging from the larger cable television networks (CATV) down to smaller satellite master antenna TV (SMATV) systems.
Advanced Television Systems Committee (ATSC) standards are an American set of standards for 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, and South Korea. Several former NTSC users, in particular Japan, have not used ATSC during their digital television transition, because they adopted their own system called ISDB.
Digital Video Broadcasting - Satellite - Second Generation (DVB-S2) is a digital television broadcast standard that has been designed as a successor for the popular DVB-S system. It was developed in 2003 by the Digital Video Broadcasting Project, an international industry consortium, and ratified by ETSI in March 2005. The standard is based on, and improves upon DVB-S and the electronic news-gathering system, used by mobile units for sending sounds and images from remote locations worldwide back to their home television stations.
High-Efficiency Advanced Audio Coding (HE-AAC) is an audio coding format for lossy data compression of digital audio defined as an MPEG-4 Audio profile in ISO/IEC 14496-3. It is an extension of Low Complexity AAC (AAC-LC) optimized for low-bitrate applications such as streaming audio. The usage profile HE-AAC v1 uses spectral band replication (SBR) to enhance the modified discrete cosine transform (MDCT) compression efficiency in the frequency domain. The usage profile HE-AAC v2 couples SBR with Parametric Stereo (PS) to further enhance the compression efficiency of stereo signals.
Multimedia Broadcast Multicast Services (MBMS) is a point-to-multipoint interface specification for existing 3GPP cellular networks, which is designed to provide efficient delivery of broadcast and multicast services, both within a cell as well as within the core network. For broadcast transmission across multiple cells, it defines transmission via single-frequency network configurations. The specification is referred to as Evolved Multimedia Broadcast Multicast Services (eMBMS) when transmissions are delivered through an LTE network. eMBMS is also known as LTE Broadcast.
Packetized Elementary Stream (PES) is a specification in the MPEG-2 Part 1 (Systems) and ITU-T H.222.0 that defines carrying of elementary streams in packets within MPEG program streams and MPEG transport streams. The elementary stream is packetized by encapsulating sequential data bytes from the elementary stream inside PES packet headers.
Scalable Video Coding: (SVC) is the name for the Annex G extension of the H.264/MPEG-4 AVC video compression standard. SVC standardizes the encoding of a high-quality video bitstream that also contains one or more subset bitstreams. A subset video bitstream is derived by dropping packets from the larger video to reduce the bandwidth required for the subset bitstream. The subset bitstream can represent a lower spatial resolution, lower temporal resolution, or lower quality video signal. H.264/MPEG-4 AVC was developed jointly by ITU-T and ISO/IEC JTC 1. These two groups created the Joint Video Team (JVT) to develop the H.264/MPEG-4 AVC standard.
Multimedia Broadcast multicast service Single Frequency Network (MBSFN) is a communication channel defined in the fourth-generation cellular networking standard called Long Term Evolution (LTE). The transmission mode is intended as a further improvement of the efficiency of the enhanced Multimedia Broadcast Multicast Service (eMBMS) service, which can deliver services such as mobile TV using the LTE infrastructure, and is expected to compete with dedicated mobile/handheld TV broadcast systems such as DVB-H and DVB-SH. This enables network operators to offer mobile TV without the need for additional expensive licensed spectrum and without requiring new infrastructure and end-user devices.
A video coding format is a content representation format for storage or transmission of digital video content. It typically uses a standardized video compression algorithm, most commonly based on discrete cosine transform (DCT) coding and motion compensation. Examples of video coding formats include H.262, MPEG-4 Part 2, H.264, HEVC (H.265), Theora, RealVideo RV40, VP9, and AV1. A specific software or hardware implementation capable of compression or decompression to/from a specific video coding format is called a video codec; an example of a video codec is Xvid, which is one of several different codecs which implements encoding and decoding videos in the MPEG-4 Part 2 video coding format in software.
Layered Coding is a type of data compression for digital video or digital audio where the result of compressing the source video data is not just one compressed data stream, as in other types of compression, but multiple streams, called layers, allowing decompression even if some layers are missing.
Low Complexity Enhancement Video Coding (LCEVC) is a ISO/IEC video coding standard developed by the Moving Picture Experts Group (MPEG) under the project name MPEG-5 Part 2 LCEVC.
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