DVB-I Webinar Series
Part 3 of 3
6 April 2020
Introduction
Paul Higgs – TM-I Chair - Huawei
• DVB-C, DVB-T, DVB-S
▪ Broadcast television services
• HbbTV
▪ Add interactive elements and
ondemand content to existing
broadcast services
• DVB-IPTV
▪ Television services delivered over
managed/private IP networks
• DVB-I
▪ Broadcast television services
delivered over the Internet
Road to DVB-I
• A177 – DVB-I Service Discovery and
Programme Information
▪ The “internet channel scan” and EPG
• A168 – DVB-DASH with Low Latency
▪ Media format for linear broadband
television services (On Demand also)
• A176 – Multicast ABR (DVB-mABR)
▪ Efficient delivery of DVB DASH over IP
networks
• A178 – Targeted Advertising (DVB-
TA)
▪ Personalizing advertisements for
television services
The ecosystem
DVB-I Concepts
Program
Info
Program
Info
Service
List
Service
List
(LL) CDN
Service Service Service Service
Service
List
Discovery
DVB-I
Client
DVB-I Client
Program
Info
Program
Info
Service
List
Service
List
(LL) CDN
Service Service Service Service
Service
List
Discovery
DVB-I
Client
Part 3: DVB-I Clients
Juha Joki - Sofia Digital
Tomi Sarparanta – Sofia Digital
• Background and purpose
• Client architecture
• Client functionality
• HbbTV (Operator Application) and Android implementation
• Backend
• Additional information and lessons learned
Topics
Background and purpose
DVB-I Reference Client Background
• Work started together with DVB in January 2020
• First version was released end of January
• “Phase 1”, a stable demo meant for DVB World was completed
early March. Work is now on-going for Phase 2, due to be
completed some time in May
• Regular updates since, now at version 2.4
• Android mobiles and tablets (7, 8, 9, 10 – just try it!) and HbbTV
OpApp versions officially supported
▪ Other possible target platforms could be (but not in scope this
time): androidTV, iOS, SmartTV platforms, or anything with DVB
DASH + javascript + HTML5
• Includes a backend component to create and edit the
necessary metadata
• Publicly hosted in DVB’s GitHub, licenced under MIT license
▪ https://github.com/DVBproject/DVB-I-Reference-Client
• Easily deployed anywhere with basic web skills
• Based on the DVB-I Spec A177 – Service Discovery and
Programme Information
• The DVB-I reference client purpose is to verify the
A177 spec (service lists, content metadata,
regions, languages, and so on) can be used to
build an end-to-end solution
▪ “DVB-I is the first major specification to benefit
from DVB’s new Verification and Validation activity
that aims at accelerating the implementation of its
technologies in the marketplace”
• At this point it is not exhaustive
• It is a work in progress – as is the specification
• Many things are unfinished or not complete
• Final version will be a reference client, not
something that is meant to be used as-is, but
perhaps providing building blocks and for and
confidence in commencing a commercial
product or ecosystem
Application scope and purpose
• Work started with a simple backend component to generate
valid DVB-I Service lists and Guide data
• Existing HbbTV OpApp service list browser and DASH player
component were adapted to use DVB-I metadata formats
• Finally, Android Progressive Web Application was developed
utilizing the dash.js player (https://github.com/Dash-Industry-
Forum/dash.js/wiki)
Project development
Client architecture
• All Service provider, service list and schedule parsing is
implemented in a common codebase used by the HbbTV and
Android clients
• Reference client codebase is divided to common, android and hbbtv
directories
▪ HbbTV implementation is divided to launcher (channel list) and epg
directories
▪ Android implementation has everything in separate js-files in the js-
directory
• XML is parsed to JavaScript objects
DVB-I Reference client architecture
• Main functions of the DVB-I Reference client are divided to
three main javascript library files
▪ common.js
– Provides basic functions for date parsing, navigation, resource loading,
layout helpers, etc.
▪ dvbi-common.js
– Provides service list registry query and channel list query functions
▪ channel-common.js
– Provides TV-Anytime schedule parsing
DVB-I Reference client architecture
• Service provider list URL is implemented inside the dvbi-
common.js
• Service provider list parsing function is the
parseServiceListProvider in dvbi-common.js
• GenerateServiceListQuery in dvbi-common.js
can be used to generate a filtered service provider query
Service provider list
• Service list parsing is done in parseServiceList in dvbi-common.js
• dvbChannels-parameter in the parseServiceList function should be a HbbTV
ChannelList object
• ParseServiceList will try to match the DVB services in the DVB-I service list with
the ones that are found in the device channel list
• Android client only lists services with a DASH source, HbbTV client list services with a
DASH source and those with DVB-T/S/C source that are listed in the device channel list
• HbbTV client also lists DVB services that are not in the DVB-I service list
▪ assigned a new LCN starting from 1000 (1000 + n) and are visually different from the services listed in
the DVB-I service list
▪ This is purely a design decision – the client can be modified to work differently, to filter out premium
services, or to filter our all services not present in the DVB-I service list etc.
Service List
• Schedule information requests are always made for a single service
• Schedule response parsing implementation is found in
parseSchedule in channel-commo n.js
• Both now/next and schedule requests use the same response
schema
• Current and next program can be requested with the
now_next=true parameter
• Schedule can be requested with start and end parameters
Schedule information
Application workflow diagram
1. Application is loaded
2. Checking for pre-selected
service list is performed
3. Service list
selected/parsed
4. Main display is shown
5. User can select another
service list / open EPG /
select or tune to a DVB-
DASH or broadcast service
Sequence example
Client functionality
• Service list browser
▪ Accesses the Service list registry
server
▪ A JS function travels through a pre-
defined master service list
– Filters: regulatorlist, providername,
genre, target country, language
▪ If there’s not a previous service list
selected, this screen is the initial
view of the operational application.
From this screen the service list is
selected
▪ The selected service list is stored in
local (web)storage or as a fallback in
a cookie
Client basic functions (1/3)
DVB-I
Client
Service
List
Discovery
• Service browser
▪ Parses through the service list selected
in the service list browser
▪ In Android, only DASH-services of the
selected service list are listed
▪ In HbbTV, three types of services are
listed:
– DVB-C/S/T services installed in the TV,
and listed in the DVB-I Service list
– DVB DASH only services
– DVB-C/S/T services installed in the TV
but not listed in the DVB-I service list
▪ Allows the selections (tuning/starting)
the DVB / Live DVB DASH services
▪ Both Android and HbbTV versions use
the same service list registry and service
lists
▪ Service list includes Low Latency
sources as well from related projects
around DVB-I (ffmpeg/dashll)
Client basic functions (2/3)
Service
List A
Service
List B
DVB-I
Client
Service
List
Discovery
• EPG
▪ Content is based on the TV-Anytime specification
– Broadcast and On-line Services Search, select and rightful use of content (“TV-Anytime”);
Part3:Metadata; Sub-part 1: Phase 1 –Metadata schemas, ETSI TS 102 822-3-1 v1.11.2
(2019-06)
▪ In HbbTV there’s a Grid-based traditional EPG, accessible with the green colour key
▪ In Android there’s a list-based EPG, opened via a user interface element
• Info banner
▪ In HbbTV, the info banner is a traditional info banner displaying “Now/Next”
programming information from the TV-Anytime
▪ In Android, the user interface overlay includes info banner information as well
Client basic functions (3/3)
HbbTV Operator app vs. Android app
• Utilizes the Operator App APIs (Privileged)
▪ Enables registering additional key events like P+/P-, INFO and GUIDE for Operator application use
▪ Enables replacing some of the normal TV User interface
▪ Additional channel list management
▪ Many OpApp functionalities require agreement with the receiver manufacturer
• Info banner / Channel list browser works in “transient” and background modes
▪ Transient mode has OpApp visible for a limited time, fullscreen video is available, can be overlaid with native UI components
▪ Background mode has the OpApp in invisible mode, listening for key events
• EPG works in the “foreground” mode
▪ Works in full-screen mode, broadcast video available only heavily scaled
• Works also as a “normal” broadcast HbbTV v2 application, utilizing only normal key events like the color keys
▪ Transport stream is provided for effortless testing
• Navigation is always done with remote control key events
• HTML5 video object –based player
▪ App relies on the native DASH player on the TV – some limitations are bound to happen (i.e. the latest advancements from
dash.js player are not available)
HbbTV OpApp DVB-I Client
• What is an OpApp?
▪ Independent specification complementing HbbTV 2.0.1
– Based on HTML5, CSS, Javascript
▪ Accessed via selecting the OpApp like an HDMI input or a similar familiar access point and offers similar user controls like in a set-top box,
including:
– Channel zapping (+/-)
– Volume control (up/down)
▪ DRM and Adaptive Bitrate Streaming (ABR)
▪ UHD, HEVC, Next-gen audio, companion screens, etc.
▪ Control of the broadcaster’s HbbTV applications
• In short: takes over the regular manufacturer TV UI/UX
▪ Example functionalities/ features
– Live TV, both DVB and OTT
– Interactive Program Guide
– Operator defined channel lists
– Mini TV-guide (i.e. overlay)
– Catchup / VOD
• OpApp Service discovery is based on country and region selection during First Time Installation
• More information: https://www.hbbtv.org/wp-content/uploads/2017/12/HbbTV-SPEC-00200-003-Operator-Applications-Explained.pdf
HbbTV OpApp Client
HbbTV Service list provider selection
HbbTV Service list browser
HbbTV EPG
• PWA-style implementation
▪ Progressive Web App => offers a simple “installation” / Add to home screen functionality via a
manifest file
▪ More information: https://en.wikipedia.org/wiki/Progressive_web_application
• Lists the DVB DASH instances of services only
• Should work on any Android client (Android 7, 8, 9 and 10 tested)
• EPG is list-based instead of grid
• Landscape mode only as an PWA app
• dash.js player implementation
▪ Uses the latest stable version (https://cdn.dashjs.org/latest/dash.all.min.js)
▪ Low latency settings included
Android client
Android Service List provider selection
Android main screen with settings screens visible
Android EPG
Backend
• PHP/JS application running on a web server
• Service list registry, service lists and programme data (TV-A) are hosted in
GitHub instance and browsable in the Sofia Digital Backend server
• Example.xml is the “hard-coded/write-protected” demo service list which can
investigated and copied
• Service list creation and exporting is possible
• TV-A data is hardcoded dummy data at the moment
▪ Some sample data has been imported during the project, but proper TV-Anytime / EPG
sources are not part of this project
• Backend can be easily installed to any web server with PHP and Javascript
support
Backend
• XML can be easily
generated and
exported to
external apps /
websites
• Service list
registry editor in
progress
Backend UI
Additional information and lessons
learned
• All code is published under the DVB GitHub account’s DVB-I
Reference Client repository
• Everything made for this project is licensed under MIT
▪ Other components used have their own license models, obviously
– These mean jquery and dash.js
• Forking, commenting and contributing is welcomed
• Live demo: https://github.com/DVBproject/DVB-I-Reference-
Client
GitHub repository
▪ Parental controls
▪ Subtitles
▪ Audio switching
▪ Language options / localization / regionalization
▪ dash.js option / Low Latency settings for HbbTV as well
▪ Series signalling
▪ Service availability
▪ SD/HD/UHD switching
▪ Linked application for service playback
▪ Live Pause
▪ DRM option
▪ Other UX enhancements
Phase 2 work still going on, in the order of
appearance
• DVB-I is not rocket science, but can be implemented with well-known
internet and TV technologies
▪ HTML5 and DASH are mature technologies working fairly well in recently released
consumer devices
• Specification is easy to follow and understand
▪ TV-Anytime is a complex beast, though
• Building apps against it has proven to be a useful exercise in building an
app working in HbbTV and Android
▪ DVB-I has proven to work with a lot of devices
• Lots of interest from all around the world
Lessons learned
• GitHub repository: https://github.com/DVBproject/DVB-I-Reference-Client
• HbbTV Frontend https://stage.sofiadigital.fi/dvb/dvb-i-reference-
application/frontend/hbbtv/launcher/
• Android PWA installer https://stage.sofiadigital.fi/dvb/dvb-i-reference-
application/frontend/android/
• Android Player https://stage.sofiadigital.fi/dvb/dvb-i-reference-
application/frontend/android/player.html
• Backend for Service list generation https://stage.sofiadigital.fi/dvb/dvb-i-reference-
application/backend/
• TS file download https://cloud.sofiadigital.fi/index.php/s/qrB6MoFH5cPCDoN
• Specification https://dvb.org/?standard=service-discovery-and-programme-metadata-
for-dvb-i-services
• Sofia Digital www.sofiadigital.com
Links
End
