Every television in the UK is defined by the industry requirements in the DTG’s D-Book


The D-Book defines the requirements for every new TV and digital terrestrial television (DTT) receiver in the UK. Compliance with this technical specification protects both the industry and consumers, and is a prerequisite of Freeview Trademark Licences.

The DTG, with the support of platforms, broadcasters, manufacturers and the wider industry, has developed and published the D-Book for the last twenty years, helping to deliver an amazing viewing experience to millions of UK consumers.

The D-Book is the result of a unique industry collaboration and acts as the gateway to the UK market, delivering new functionality each year so that the viewing experience always benefits from new technologies.

Driven by industry, the D-Book is open, democratic and supportive of public policy. Industry expert groups continually update and peer-review the specification so that it drives the UK TV market towards innovation, delivering real economic value in this vital industry.

The DTG Council thanks the DTG team and all our industry experts for their insight and invaluable contribution which sustains the UK’s world-leading position in television.

D-Book cover

D-Book 9 Highlights

The DTG’s D-Book 9 was published in November 2016 and introduced the HbbTV references necessary to transition from MHEG for the UK DTT Platform interactive services. It includes support for High Dynamic Range and mandated use of HEVC for HD IP delivered services to pave the way to UHD.

Pete Sellar, Associate Director, Broadcast, at the DTG said: “This year’s new developments ensure that the D-Book continues to support Digital UK and all UK DTT-based platforms including Freeview Play, Freeview HD, YouView, EETV, NowTV and the UK DSAT platform, Freesat, as well as several international adaptations. DTT delivers to the largest viewing audience and remains fundamental to the distribution of content and entertainment.”

“The industry’s not-for-profit test centre, DTG Testing, continues to offer conformance tests and testing services in support of Freeview HD and Freeview Play and we continue to ensure European harmonisation wherever possible, while meeting the needs of the rapidly developing and highly successful UK TV market.”


The first edition of the D-Book was written in 1996 when the current UK standard for terrestrial broadcasting (DVB-T) was new and untried. Early editions of the D-Book enabled the publication of the European digital TV specification: the E-Book.

Through the publication of later editions, D-Book has introduced to the UK DTT market HD and DVB T2, MHEG developments in support of the PSB catch-up players, interoperability standards in support of the early launch of Freeview Play, and features to support the future 700 MHz clearance. In addition, the work carried out in the DTG ahead of the publication of D-Book 7 Part B formed a major input into the internationally developed HbbTV specification.

D-Book 8 was published in March 2015, superseding D-Book 7 Part B, much of which was incorporated into HbbTV. D-Book 8 provided support for the new Freeview Play service, clearance of the 700Mhz band, smart retune to protect user settings during channel changes, over-the-air signalling of software updates via IP, and a standard method for displaying signal strength and quality.

  • D-Book 9 is only available to DTG members.