Encrypted Media Extensions (EME) is a W3C specification for providing a communication channel between web browsers and digital rights management (DRM) agent software. This allows the use of HTML5 video to play back DRM-wrapped content such as streaming video services without the need for third-party media plugins like Adobe Flash or Microsoft Silverlight. The use of a third-party key management system may be required, depending on whether the publisher chooses to scramble the keys.
Contents
EME is based on the HTML5 Media Source Extensions specification, which enables adaptive bitrate streaming in HTML5 using e.g. MPEG-DASH with MPEG-CENC protected content.
EME has been highly controversial because it places a necessarily proprietary, closed component into what might otherwise be an entirely open and free software ecosystem.
Support
In April 2013, on the Samsung Chromebook, Netflix became the first company to offer HTML5 video using EME.
As of 2016, the Encrypted Media Extensions interface has been implemented in the Google Chrome, Internet Explorer, Safari, Firefox, and Microsoft Edge browsers.
While backers and the developers of the Firefox browser were hesitant in implementing the protocol for ethical reasons due to its dependency on proprietary code, Firefox introduced EME support on Windows platforms in May 2015. Firefox's implementation of EME uses an open-source sandbox to load the proprietary DRM modules, which are treated as plug-ins that are loaded when EME-protected content is requested. The sandbox was also designed to frustrate the ability for services and the DRM to uniquely track and identify devices.
Netflix supports HTML5 video using EME with a supported browser: Chrome, Firefox, Microsoft Edge, Internet Explorer (on Windows 8.1 or newer), or Safari (on OS X Yosemite or newer). YouTube supports the HTML5 MSE. Available players supporting MPEG-DASH using the HTML5 MSE and EME are THEOplayer by OpenTelly, the bitdash MPEG-DASH player, dash.js by DASH-IF or rx-player.
Version 4.3 and subsequent versions of Android support EME.
Criticism
EME has faced strong criticism from both inside and outside W3C. The major issues for criticism are implementation issues for open-source browsers, entry barriers for new browsers, lack of interoperability, concerns about privacy and accessibility and possibility of legal trouble in the United States due to Chapter 12 of the DMCA. Many of these issues arise because of lack of specification of the Content Decryption Modules (CDMs).