What a truly exciting world we live today. The acceleration and usability of mobile computing devices is reshaping how everyone thinks about information, entertainment and business. I personally have been thinking about disruptive video technologies for a very long time, from LaserDisc, WebTV, Internet and everything we’ve accomplished since I joined Adobe. I’m surrounded by an incredible team of thinkers and doers who have significantly advanced the way people and businesses create and deliver video in the past 5 years.
With any accelerated technology – a large group of people are motivated to consider different ideas and concepts that improve the technology, and as such when you are smack in the middle, there are a lot of options available to you.
Online video today is smack in the middle of this — lots of ideas, lots of execution, lots of trial and error. Questions such as video file format, protection, delivery, optimizations for different networks and different device capabilities. At first glance is a lot to handle, and it is amazing to have so many great thinkers considering new ideas and pushing the envelope to mature the industry quickly so we can all realize its true potential.
Today we have made a small step towards thinning down the fragmentation. In a unique cooperation, Adobe with the Microsoft media team, have jointly contributed to a whitepaper sharing our thoughts on Video Streaming file format optimized for online delivery using fragmented MPG4 file format (fMP4) Part 12.
The file format for online streaming is a very important component of a great user experience. The online streaming file format is what makes it possible to deliver high-quality experiences over the Internet and evolving mobile networks. Traditional formats such as MPEG2 used in broadcast and on DVD’s are a terrific option for those mediums, but has significant challenges when publishing video online. Problems such as multi-track audio, multiple camera angles, seamless and dynamic Ad insertion, network and storage optimizations and high performance bitrate switching (adaptive bitrate) are all unique to online.
This paper highlights the technical and consumer benefits of the fMP4 format chosen by both Adobe and by Microsoft for their online HTTP streaming formats. I’ve pulled out some key highlights of the fMPEG4 format from the paper when compared with other streaming formats being used in the market today.
- Content Metadata Separation – This enables multi-camera switching – think about that sporting event which lets you switch between the bench camera, the roof camera and the broadcast feed. The format improves online stream switching functions that can create a great interactive video experience.
- Backwards Compatibility to MPEG2 – Video needs to be distributed to multiple devices, with multiple formats – publishers will need to consider how to deliver to both MPEG2-TS/HLS and devices supporting fMP4. A key benefit of the fMP4 format is it is really easy to change the file format structure. Both Adobe and Microsoft achieve this with Adobe Flash Media Server 4.5 and with Microsoft IIS.
- Independent Track Storage – Accessibility is an absolute requirement for online video to support audiences with different capabilities. The file format can make this effort simple or difficult, and fMPG4 makes it easier. The format also enables more advanced functions such as switching languages, or switching different audio feeds for live events.
- Seamless Stream Splitting – Adaptive bitrate is a solution for delivering HD content over the internet. Great adaptive bitrate implementations will not disrupt the viewer experience. The fragmented MP4 format supports smaller segment sizes (1-2 sec compared with 10sec for TS) and makes it possible to very quickly switch between bitrates so your viewer is not interrupted.
- TrickPlay Modes – Trick play allows the user to navigate their live or vod video content using DVD or DVR functionality such as fast and superfast forward or reverse play. This is much easier when you have the content on a DVD or local DVR, but it is a real hard problem to solve when media is not local. The fMPG4 format structure provides the foundation to support this user experience.
- Integrated DRM – Content protection options are critical to secure content so broadcasters can make more content available online. fMP4 support for integrated DRM models enables the broadcaster to develop their online business offering resulting in more content for consumers.
Adobe’s F4F file format is an HTTP streaming format based on the fragmented MP4 file format. This format is deployed today at service providers such as Akamai, Limelight and Level3, and is used today by broadcasters such as the BBC and MTV . The Open Source Media Framework, combined with Adobe Flash Player is our player supporting this format, and we have published the full format spec on Adobe.com.
You can read a lot more technical and application-specific information about the fragmented MP4 file format in Tim Siglin’s whitepaper in which media researchers from both Adobe and Microsoft were joined by Netflix to comment on the fragmented MP4 file format. In the paper, you can also discover industry standards groups being formed including MPEG-DASH and UltraViolet/DECE. These standards groups are committed to defining video delivery and protection standards to reduce the fragmentation in the market so broadcasters can reduce their costs to publish content and publish more great content online and across all consumer devices.
In addition, you can also review Chris Knowlton’s blog post from Microsoft where he has shared his perspective on this paper and the decisions made in the development of the Protected Interoperable File Format (PIFF) used within IIS Smooth Streaming.
The writer, Tim Siglin is from Transitions, Inc, and is a well-published streaming media industry analyst and reporter.
To read this paper and discover the opportunities available to the market with this file format, please download “Unifiying Global Video Strategies – MP4 File Fragmentation for Broadcast, Mobile and Web delivery” Please connect to Tim Siglin’s Blog posting .