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Firefox Add-One based on WebExtensions

Embracing such Hybrid Interactive TV Technologies:

           

Preamble

This extension for CHROME mimics the behavior of the good one called FireHbbTV available only for FIREFOX

I have decided to do it, as at work we are only using CHROME as a development tool on a daily basis and I am now used to it. And at last I also wanted CHROME to avoid to download such iTV (interactive television) application pages (exposed by an URL or embedded inside a broadcast transport stream)

Features

Feature Description
auto-detection an analysis of HTTP server headers plus inside header & meta tags is performed
forced detection user on-clicked extension icon will force its iTV emulation (auto-saved too)
bottom status bar underneath the screen rendering, the emulator is providing some buttons (colored keys, resolutions for zoomed rendering, ...)
iDTV customization the extension enables customization of various parameters (user-agent, OIPF capabilities, country, CAS id, DVB channels, ...)
external inputs it handles some external inputs such as CI+ APDU reply message, Stream-Event content customization & triggering, DVB channels with customized LCN, ...
video support it will handle the rendering of CHROME unrecognized broadcast video stream: Mpeg-TS and Mpeg-DASH

Status

  • ✅ removing CHROME warning popups for various undefined mime-types
  • 🚧 currently only as a prototype stage but the proof of concept has been validated
  • 💀 SUN MHP technology has been put aside as it will need to have a JVM installed with its associated plugin (a mess to install and moreover this technology is now replaced by the brand new one called HbbTV) I know GINGA is MHP based and still present in South America but for how long ...
  • 📡 DVB-SI/PSI tables (such as EIT & AIT) extraction inside MPEG-TS files, will be handle by an external Chrome application
  • 📼 MP4 Transport Stream video (without DRM) might be supported using an external library:
    • will have to investigate 🔍 upipe Chrome NaCl rendering plugin
    • might also have a look at Video.JS library handling also HLS and DASH
  • ✂️ OIPF technology will not be fully implemented (only the HbbTV subset will be done)
  • HbbTV V2.0 might be present (with an exposed WebSocket server) when V1.5 implementation will be done
    • for the meantime, look at node-hbbtv from the well-known Fraunhofer (creator of MP3)
  • CI+ HbbTV implementation is hereby emulated with a default code (can be customized)
  • Remote control colored keys will be mapped to specific keyboard keys (R,G,B,Y) and external Apple Remote Control will be taken into account (maybe also Win/LIRC)
  • A dedicated tab might be added in Chrome Web Inspector for user debugging purpose
  • ⚠️ For developers, if you want to use this extension by yourself, you will need to unlock NaCL feature in Chrome
  • 📆 Soon this extension will be published on CHROME store
This extension might use a CHROME application in the future in order to have video and EIT handled
(like Mpeg-TS and Mpeg-DASH properly played inside the browser)

Detection and usage

In order to automatically activate the extension on an given web page, you need to follow standard implementation as seen for example on SAMSUNG iDTV devices that are looking for this HTTP header field:

Content-Type: application/vnd.hbbtv.xhtml+xml

This HTTP header response is coming from the server side where the page is hosted as you can see with such UNIX command:

curl -I http://www.arte.tv/redbutton/index.html
... (HTTP headers)

You can also add a defined META tag inside your page:

Technology META tag
HbbTV <meta http-equiv="content-type" content="application/vnd.hbbtv.xhtml+xml; charset=UTF-8" />
CE-HTML <meta http-equiv="content-type" content="application/ce-html+xml; charset=UTF-8" />

and sometime with the addition of a given DOCTYPE:

Technology DOCTYPE tag
HbbTV <!DOCTYPE html PUBLIC "-//HbbTV//1.1.1//EN" "http://www.hbbtv.org/dtd/HbbTV-1.1.1.dtd" >
BML <!DOCTYPE BML PUBLIC "+//ARIB STD-B24:1999//DTD BML Document//JA" "http://www.arib.or.jp/B24/DTD/BML_1_0.dtd" >

In other cases, you can also manually click on the extension icon inside CHROME's bar to force the page to be interpreted as an Hybrid iDTV page. (this action is saved in local storage for further visits)

Examples

The purpose of this extension is mainly to validate the MIT-xperts test suite under CHROME. Here are some example URL that have been extracted from various sources:

Name Source URL
MIT-xperts HbbTV test suite TS stream http://itv.mit-xperts.com/hbbtvtest/
ARTE HbbTV French DTT TS http://www.arte.tv/redbutton/
ARTE CE-HTML Philips iDTV portal http://cehtml.arte.tv/de/2764896.cehtml

Abbreviations

  • iDTV: Integrated Digital TeleVision
  • CI+: Common Interface
  • HLS: HTTP Live Streaming
  • DASH: Dynamic Adaptive Streaming over HTTP
  • DVB: Digital Video Broadcasting
  • DVB-T: Digital Video Broadcasting Terrestrial
  • DVB-C: Digital Video Broadcasting Cable
  • DVB-S: Digital Video Broadcasting Satellite
  • DVB-SI: DVB Service Information
  • AIT: Application Information Table
  • EIT: Event Information Table
  • LCN: Logical Channel Number

References

  • MHP (Multimedia Home Platform) : Based on SUN JAVA technology working on GEM-MHP middleware
  • HbbTV (Hybrid Broadband Broadcast TeleVision) :
    • defined by current ETSI TS 102 796 V1.3.1 specifications (aka HbbTV V2.0)
    • following old MHP AITX structure
    • handling some CEA-2014 notations
    • implementing a subset of OIPF objects
  • OHTV (Open Hybrid TV) : similar to HbbTV and used for example at iCON TV in KOREA by the national broadcaster KBS since 2010
  • BML (Broadcast Markup Language) : similar to HbbTV and defined by ARIB STD B-24 standard used in JAPAN over ISDB-T broadcasted channels like NHK
  • CE-HTML (Consumer Electronics HTML) : nowadays less used and only found on old devices
  • OIPF (Open IPTV Forum) : used on some STB and since 2014 activities have been transfered to HbbTV association

License

[The MIT License][0] [0]: http://opensource.org/licenses/MIT