Globally Executable MHP (GEM) is a DVB specification of a Java based middleware for TV broadcast receivers, IPTV terminals and Blu-ray players. GEM is an ETSI standard (ETSI TS 102 819, ETSI TS 102 728) and an ITU "Recommendation” (ITU-T J.202). GEM defines a set of common functionalities which are independent from the signaling and protocols of a specific transmission network and enables to write interoperable Java applications for TV. GEM is not intended to be directly implemented, but rather forms the basis for broader specifications targeting a particular network infrastructure (e.g. US cable) or class of device (e.g.

Blu-ray Disc The Blu-ray Disc (BD), often known simply as Blu-ray, is a Digital media, digital optical disc data storage format. It was invented and developed in 2005 and released on June 20, 2006 worldwide. It is designed to supersede the DVD format, and c ...

players). GEM defines profiles for different device classes (targets) these define the set of available features of GEM for this device class. Currently GEM defines targets (API profiles) for broadcast, packaged media (Blu-Ray) and IPTV. Combinations of these targets can be combined into a hybrid GEM platform, which enables to build devices with multiple network interfaces, such as a combined broadcast/IPTV set-top box.

History

A few years ago, the DVB project started the development of a Java-based application platform (a set of APIs), called MHP, intended to support software applications running on digital television platforms. Such applications could include Electronic Program Guides (EPG's), interactivity, Video on Demand (VOD), email through your television, etc. The MHP specification defines the download of MHP applications ("

xlets An Xlet is very similar to a Java applet and is originally introduced in Sun Microsystems's Java TV specification to support applications for Digital TV. Though Xlet looks superficially different from other application models in Java such as applet ...

") over transmission networks based on other DVB specifications (i.e. over-the-air or terrestrial networks using

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 Febr ...

, satellite networks using

DVB-S Digital Video Broadcasting – Satellite (DVB-S) is the original DVB standard for Satellite Television and dates from 1995, in its first release, while development lasted from 1993 to 1997. The first commercial applications was by Star TV in Asia ...

, cable networks using

DVB-C Digital Video Broadcasting - Cable (DVB-C) 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 ...

). As other specification bodies such as CableLabs and the

Blu-ray Disc Association The Blu-ray Disc Association (BDA) is the industry consortium that develops and licenses Blu-ray Disc technology and is responsible for establishing format standards and promoting business opportunities for Blu-ray Disc. The BDA is divided into ...

chose to base their own DTV software standards on MHP it became necessary to define a subset of MHP which removes the transmission-related elements of the MHP specification but retains the application API's, thus allowing broad content compatibility across a range of delivery platforms. In January 2010, the DVB project made GEM the primary middleware specification and released a self-contained version of GEM in ETSI TS 102 728, citing MHP only as one of many already-existing implementations.

Platforms

At the time of writing, the following platforms are defined, which base on/extend GEM: * the Multimedia Home Platform (MHP), the open, multi-platform middleware specification developed by the DVB project, * the OpenCable Application Platform (OCAP / tru2way), which is an Interactive television (iTV) middleware software layer for US cable, * the Advanced Common Application Platform (ACAP) from North America's

ATSC 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 ...

, * GEM-IPTV, a version of GEM developed by DVB intended for telco-based networks, * the ARIB B.23 specification from Japan's ARIB, * the PAE specification in the Open IPTV Forum, * BD-J the Java-platform for the

. As all these platforms are based on the common GEM-core, making it possible to write Java applications that will run interoperably on all these systems.

External links

Official GEM and MHP website

Digital Video Broadcasting

European Telecommunications Standards Institute

References

{{DEFAULTSORT:Globally Executable Mhp Java platform Digital television Interactive television Blu-ray Disc

History

Platforms

See also

External links

References