What You Should Know About Video and HTML5
The latest web standards enable a whole new approach to delivering multimedia content. But for now, they still require some workarounds for unresolved issues. HTML5 offers significant advantages for service providers who want to satisfy growing demand for high-quality delivery of multimedia content across a rapidly expanding range of devices. This new generation of Web standards enables more compelling user interfaces. It establishes standard methods for embedding video within a web page. And it streamlines development of cross-platform applications that can reach more customers, while providing consistent performance across desktop computers, mobile tablets and smartphones. Although HTML5 is still in the early stages of deployment, its specifications have the potential to transform how multimedia content is consumed. For example, enhanced user interfaces can play a key role in attracting premium users for paid content services. New video capabilities are likely to promote increased viewing of online video using a standard web browser. And more uniform development methods will help service providers overcome the fragmentation that has been a key barrier to multiscreen video capabilities. To take advantage of these opportunities, service providers need to introduce HTML5 enhancements seamlessly, and this process must be based on an understanding of significant video issues that have not yet been resolved. In particular, HTML5 does not currently recommend a specific video codec. It does not provide guidance or restrictions on digital rights management (DRM). And its cross-browser video support is limited to progressive downloads — and does not support adaptive/live HTTP streaming. In addition, HTML5 does not address a variety of video advertising formats. Work is still underway to resolve these issues before HTML5 specifications are finalized. In the meantime, service providers can deploy solutions that address the remaining complexities. The most effective approaches will consider the multimedia delivery architecture that is already in place, as well as the provider’s strategic objectives for the future.
Expanded web browser capabilities
- Video — HTML 5 defines a standard way to embed video on a web page, using the <video> element, with no need for additional plug-in software like Flash, Silverlight and QuickTime to run the video. This method supports a variety of video control capabilities, for play, pause and loading, as well as duration, volume and seeking.
- Multiscreen — HTML5 helps service providers deliver a broader range of features to smartphones and tablets. Since iOS does not support Flash technology, these web standards offer a key solution for reaching the iPad, iPhone and Android devices, without generating serious error messages.
- User interfaces — Smartphones and tablets have raised the mobile user experience to a new level. Now HTML5 allows service providers to add livelier, more attractive enhancements, including dynamic, scriptable rendering of 2D shapes and images, creation of 3D animations, sliders and drag-and-drop effects.
- Advanced API definition — An array of user interface APIs defined in HTML5 can enrich web page capabilities by allowing them to access content stored locally on a user’s devices. The APIs include offline storage, 2D graphics capabilities, video/audio streaming, geolocation and access to the phone's camera.
- Discovery model — HTML5 web applications are essentially websites that can be viewed in a browser. This provides a convenient alternative to working through app stores, and users do not have to download each application, install it on a physical device and maintain the latest versions.
By supporting these new capabilities and using them to build compelling offerings, service providers can deliver a richer user experience, across a broad range of desktop computers, tablets and smartphones. However, the issues discussed in the following sections remain unresolved, presenting some obstacles to HTML5’s goal of enabling simplified multimedia delivery.
Unresolved encoding issues
To play a video, a browser needs to support its codec. But so far, the W3C HTML Working Group has been unable to select a royalty-free video codec that satisfies everyone. As a result, HTML5 specifications do not currently provide recommendations for which video codec to support. Unfortunately, there is no single web browser that currently supports all codecs (Table 1). Previously, Google Chrome supported all formats. However, H.264 support will be phased out in HTML5, while the focus shifts to WebM and Ogg Theora. Support for other high-quality open codecs may be added in the future.
As a result of this fragmentation, video service providers must be able to encode content in multiple formats in order to capture as many viewers as possible.
Ongoing discussions on DRM
HTML5 specifications do not currently provide either guidance or restrictions on the use of DRM. The W3C HTML Working Group has been cautious on this topic, allowing relevant stakeholders to initiate options for considerations. One option is to handle the issue through a codec implementation; for example, by using dedicated plug-ins. More recently, engineers at Microsoft, Netflix and Google have proposed an alternative to DRM, which they describe as an extension to the media streaming capability that would use encryption to protect copyrighted content. For now, DRM is essential for service providers who deliver commercial video services. Therefore, each provider must develop its own methods of implementation, based on existing infrastructure, key business objectives and the expectations of content partners.
Limited support for streaming
Service providers also need to be aware of that cross-browser HTML5 video support is limited to progressive downloads, and the specifications neither support nor prevent the use of adaptive/live HTTP streaming. Clearly, a service provider’s delivery chain must take these HTML5 specifications into consideration, along with current browser and video player capabilities. Some web browsers may provide extensions for handling adaptive/live HTTP streaming. Safari, for example, delivers H.264 files that are chunked over HTTP. Some service providers combine these capabilities with live Flash streaming, as a fallback for iOS devices. For adaptive bitrate streaming, an HTML5 video player can only perform one bandwidth check message before streaming begins. This message is used to test the viewer’s bandwidth and deliver the video stream. However, once streaming is underway, the player cannot check the connection quality to dynamically adapt the video file. With this limitation, video service delivery may only be possible for consumers who have high-quality bandwidth, which reduces the revenue potential. In order to actually measure and/or influence adaptive streaming behavior, only Firefox has vendor-specific support for the number of frames parsed, decoded and presented such as:
- Network performance: bandwidth, latency
- Client performance: frames decoded/dropped, bytes decoded
- Video buffering: occurances, duration, reason
- Stream adaptation: switches, new/old quality level, reason
Adjustments needed for ads
Although some ad networks and ad servers already comply with HTML5, a variety of advertising mechanisms, such as pre-roll and overlay advertising formats, are not included in the standards. Mid-roll and clickable ads are not supported, and ABR limitations may also affect ad delivery. These limitations all reduce the monetization potential of video services, so providers will need to implement proprietary mechanisms as alternatives.
HTML5 standards open exciting opportunities for creative web applications and new ways of delivering video to subscribers anywhere, on any device. At this time, specifications have not been finalized, but implementation is already underway. For now, service providers who want to leverage HTML5 opportunities need to keep in mind that delivery scenarios for video and advertising are in flux, and their solutions should be adaptable as the HTML5 ecosystem evolves. At times, it may be necessary to combine a mix of technologies to address key markets and enable crucial capabilities. For example, HTML5 video is most valuable, right now, for iOS devices that do not support Flash technologies. But each service provider must assess the value of HTML5 opportunities and costs within an overall multimedia delivery strategy. These issues are most critical for content service providers. Alcatel-Lucent offers a Player Development Kit (PDK) on top of the Multiscreen Video Platform solution, which can help overcome hurdles linked to HTML5 video services integration and reduce the lead time required for customized cross-platform applications. To contact the author or request additional information, please send an email to email@example.com.