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Scalable Video Multicast
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 Addr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multicast
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. Group communication may either be application layer multicast or network-assisted multicast, where the latter makes it possible for the source to efficiently send to the group in a single transmission. Copies are automatically created in other network elements, such as routers, switches and cellular network base stations, but only to network segments that currently contain members of the group. Network assisted multicast may be implemented at the data link layer using one-to-many addressing and switching such as Ethernet multicast addressing, Asynchronous Transfer Mode (ATM), point-to-multipoint virtual circuits (P2MP) or InfiniBand multicast. Network-assisted multicast may also be impl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MBMS
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 (Long Term Evolution) network. eMBMS is also known as LTE Broadcast. Target applications include mobile TV and radio broadcasting, live streaming video services, as well as file delivery and emergency alerts. Questions remain whether the technology is an optimization tool for the operator or if an operator can generate new revenues with it. Several studies have been published on the domain identifying both cost savings and new revenues. Deployments In 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVB-H
DVB-H (Digital Video Broadcasting - Handheld) is one of three prevalent mobile TV formats. It is a technical specification for bringing broadcast services to mobile handsets. DVB-H was formally adopted as ETSI standard EN 302 304 in November 2004. The DVB-H specification (EN 302 304) can be downloaded from the official DVB-H website. From March 2008, DVB-H is officially endorsed by the European Union as the "preferred technology for terrestrial mobile broadcasting". The major competitors of this technology are Qualcomm's MediaFLO system, the 3G cellular system based MBMS mobile-TV standard, and the ATSC-M/H format in the U.S. DVB-SH (Satellite to Handhelds) now and DVB-NGH (Next Generation Handheld) in the future are possible enhancements to DVB-H, providing improved spectral efficiency and better modulation flexibility. DVB-H has been a commercial failure, and the service is no longer on-air. Ukraine was the last country with a nationwide broadcast in DVB-H, which began trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WiMAX
Worldwide Interoperability for Microwave Access (WiMAX) is a family of wireless broadband communication standards based on the IEEE 802.16 set of standards, which provide physical layer (PHY) and media access control (MAC) options. The WiMAX Forum was formed in June 2001 to promote conformity and interoperability, including the definition of system profiles for commercial vendors. The forum describes WiMAX as "a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL". IEEE 802.16m or WirelessMAN-Advanced was a candidate for 4G, in competition with the LTE Advanced standard. WiMAX was initially designed to provide 30 to 40 megabit-per-second data rates, with the 2011 update providing up to 1 Gbit/s for fixed stations. WiMAX release 2.1, popularly branded as WiMAX 2+, is a backwards-compatible transition from previous WiMAX generations. It is compatible and interoperable with TD-LTE. Terminology WiM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LTE (telecommunication)
In telecommunications, long-term evolution (LTE) is a standard for wireless broadband communication for mobile devices and data terminals, based on the GSM/EDGE and UMTS/HSPA standards. It improves on those standards' capacity and speed by using a different radio interface and core network improvements. LTE is the upgrade path for carriers with both GSM/UMTS networks and CDMA2000 networks. Because LTE frequencies and bands differ from country to country, only multi-band phones can use LTE in all countries where it is supported. The standard is developed by the 3GPP (3rd Generation Partnership Project) and is specified in its Release 8 document series, with minor enhancements described in Release 9. LTE is also called 3.95G and has been marketed as "4G LTE" and "Advanced 4G"; but it does not meet the technical criteria of a 4G wireless service, as specified in the 3GPP Release 8 and 9 document series for LTE Advanced. The requirements were set forth by the ITU-R organisation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVB-T
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 (COFDM or OFDM) modulation. It is also the format widely used worldwide (including North America) 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. Basics Rather than carrying one data carrier on a single radio frequency (RF) channel, COFDM works by splitting the digital data stream into a large number of slower digital streams, each of which digitally modulates a set of closely spaced adjacent sub-carrier frequencies. In the cas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MediaFLO
MediaFLO was a technology developed by Qualcomm for transmitting audio, video and data to portable devices such as mobile phones and personal televisions, used for mobile television. In the United States, the service powered by this technology was branded as FLO TV. Broadcast data transmitted via MediaFLO includes live, real time audio and video streams, as well as scheduled video and audio clips and shows. The technology could also carry Internet Protocol datacast application data, such as stock market quotes, sports scores, and weather reports. In October 2010, Qualcomm announced it was suspending new sales of the service to consumers. In December 2010, AT&T announced that it will purchase Qualcomm's FCC licenses in the 700 MHz band. FLO TV discontinued service on March 27, 2011. Overview The "FLO" in MediaFLO stood for ''Forward Link Only'', meaning that the data transmission path is one way, from the tower to the device. The MediaFLO system transmitted data on a frequ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qualcomm
Qualcomm () is an American multinational corporation headquartered in San Diego, California, and incorporated in Delaware. It creates semiconductors, software, and services related to wireless technology. It owns patents critical to the 5G, 4G, CDMA2000, TD-SCDMA and WCDMA mobile communications standards. Qualcomm was established in 1985 by Irwin M. Jacobs and six other co-founders. Its early research into CDMA wireless cell phone technology was funded by selling a two-way mobile digital satellite communications system known as Omnitracs. After a heated debate in the wireless industry, the 2G standard was adopted with Qualcomm's CDMA patents incorporated. Afterwards there was a series of legal disputes about pricing for licensing patents required by the standard. Over the years, Qualcomm has expanded into selling semiconductor products in a predominantly fabless manufacturing model. It also developed semiconductor components or software for vehicles, watches, laptops, wi- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scalable Video Coding
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 form of layered coding). 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 (smaller screen), lower temporal resolution (lower frame rate), 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. Overview The objective of the SVC standardization has been to enable the encoding of a high-quality video bitstream that contains one or more subset bitstreams that can themselves be decoded with a complexity and reconstruction quality similar to that achieved using the existi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Layered Coding
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. Overview With layered coding, multiple data streams or layers are created when compressing the original video stream. This is in contrast to other types of compression, where the result is typically a single data stream. During decompression, all layers can be combined to recreate the original video stream. Additionally, the stream can be decoded even if some layers are missing (though usually a layer hierarchy has to be respected, with a base layer that must available). If layers are missing, the resulting stream will have reduced visual quality, but will still be usable. Use cases Layered coding is helpful when the same video stream needs to be available in different qualitie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LCEVC
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. Concept LCEVC specifies an enhancement layer which, when combined with a base video encoded with a separate codec, produces an enhanced video stream. The base layer is decodable by a hardware decoder, and the enhancement layer is suitable for software processing implementation with sustainable power consumption. The enhancement layer provides improved features to existing codecs, such as compression capability extension and lower encoding/decoding complexity, for live streaming or broadcasting applications. LCEVC leverages a base video codec (e.g., AVC, HEVC, VP9, AV1, EVC or VVC) and employs an efficient low-complexity enhancement that adds up to two layers of encoded residuals, along with normative signalled up-sampling methods, that correct artifacts produced by the base video codec and add deta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Efficiency Video Coding
High Efficiency Video Coding (HEVC), also known as H.265 and MPEG-H Part 2, is a video compression standard designed as part of the MPEG-H project as a successor to the widely used Advanced Video Coding (AVC, H.264, or MPEG-4 Part 10). In comparison to AVC, HEVC offers from 25% to 50% better data compression at the same level of video quality, or substantially improved video quality at the same bit rate. It supports resolutions up to 8192×4320, including 8K UHD, and unlike the primarily 8-bit AVC, HEVC's higher fidelity Main 10 profile has been incorporated into nearly all supporting hardware. While AVC uses the integer discrete cosine transform (DCT) with 4×4 and 8×8 block sizes, HEVC uses integer DCT and DST transforms with varied block sizes between 4×4 and 32×32. The High Efficiency Image Format (HEIF) is based on HEVC. , HEVC is used by 43% of video developers, and is the second most widely used video coding format after AVC. Concept In most ways, HEVC is an extensi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
