Tuesday, December 27, 2011

Adaptive Bitrate Technology: Meeting the Multi-Screen Challenge Head On – Matt Smith, Envivio

As the demand to deliver content to consumers on multiple screens continues to grow at a rapid pace, companies adapt their methods and means to meet the challenge. It's no longer a notion or idea on the horizon – but a mandate for many product and services in a multi-platform world, where consumers want any content on any device, anytime and anywhere. This is both exciting and worrisome for service providers and content owners – but new trends and tactics like adaptive bit rate (ABR) streaming is changing it all and making it easier to deliver content, says Matt Smith, VP of Internet Television Strategy & Solutions at Envivio.

Smith attributes the accelerated change of multi-screen delivery to the "hockey stick effect" of mobile video viewing trends. He cites Cisco's Visual Networking Index: Forecast that says, "By 2014, all forms of video will constitute 91% of global consumer Internet traffic." (from Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update, 2010–2015  [Visual Networking Index] - Cisco Systems)

Adapting to ABR 
"Adaptive bit rate encoding has been around for a few years," says Smith, "but we're really starting to see some increased uptake as broadcasters and content providers fully embrace the TV Everywhere experience. We're seeing true convergence happening."
ABR streaming was first developed by Move Networks and is now offered in several different flavors by Adobe Systems (HTTP Dynamic streaming), Apple (HTTP Live Streaming) and Microsoft (Smooth Streaming). It works by taking a single source video and encoding it at multiple bit rates. When the video is requested over the network, the content adapts to the network not the network adapting to the content. A user's bandwidth and CPU capacity is detected in real time and the quality of a video stream adjusts according to the changing conditions. 

Each bit rate version is sliced up into tiny fragments and the video player pulls fragments from the different encoded versions and inserts them into the stream as bandwidth dictates. The result is faster video start times with little or no buffering which translates to better viewing experiences. (From Skytide Insight for CDNs - Adaptive Bitrate Streaming)

According to Smith:

"Adaptive bit rate gives some commonality amongst these formats, (from Adobe, Apple and Microsoft), [and] all have common codec payloads in AVC and AAC. So what we're able to do is create a common encoding experience so instead of creating every stream rendition on the encoder, we're creating resolution renditions and delivering those to the network where we catch it (if you will) in what's called a network media processor (NMP)."
Envivio's Halo product is a NMP that can take in 50 different channel renditions and output thousands of streams. A NMP is very beneficial for CDNs and has other functions like DRM, content encryption, ad detection and insertion, television ratings to closed captions. Smith says the NMP stage is the next evolution of ABR and network functionality where the customer/operator is given a lot of scale. Smith added that traditional method of streaming, in which encoder creates multiple renditions, is still very valid for operators with only a few channels. But for those operating multiple channels, this is a new and dynamic approach that they'd want to consider.

Smith advises that for content owners, all screens are a MUST HAVE, and says:
"If your media strategy excludes screens, revisit your strategy. There is no one platform or group of users you should exclude. Channel growth will exacerbate the problem – number of screens will increase."
Smith shared the following points in Adapting to ABR:
• Enables experiences/resolutions -­ mobile to HD
  – Better QoE for viewers/users
  – Adds complexity: additional renditions/screens
• Chunked formatting/delivery
  – Boundaries  and chunk lengths vary by format
• Video & audio payload similar between formats
  – AVC/H.264 -­‐ Video
  – AAC -­‐ Audio
‘Hey Matt - is there one universal codec?'

That was a real question an unnamed Yahoo! Engineer asked Smith in 2003, and almost 10 years later it still brings a smile to his face. Smith has been involved in every aspect of digital video systems design, compression, workflows and delivery for 15+ years, having worked with industry leaders like NBC, Yahoo!, Inlet Technologies and Cisco. He recounts how in the past, different workflows were created for the different streaming environments. There was one for web, one for mobile, one for television and for a variety of reasons there were multiple streaming formats. Hence the best question of career which he says has gotten a lot of laughs over the years. 

Smith says, laugh if you will but where we are today with ABR and the common payload of AVC/H.264 video and AAC audio, it has enabled these chunked ABR type experiences creating the option to do common encoding within a M2TS wrapper to generate multiple renditions on one small platform, and enable a lot of scale. 

Key Takeaways…

Smith says that with ABR, you're essentially creating similar number of streams, but in a different part of the network. You get significant scale gains and you should plan to deliver to every possible screen. The workflow not for every organization and where channel count is low, "old" models work. 

It's about moving from live to live: file to live, live to file. ABR allows for real time packaging (think about… request for right device at the right time) and request based delivery, runtime encoding and delivery. The benefits of a NMP as origin server provides value beyond is packaging and assists with cache.  Smith sees ABR and NMP solutions as key technologies to help service providers and content owners meet the multi-screen challenge on head on and win.

About Envivio
Envivio is a leader in solutions for multi-screen video-over-IP delivery. We design our solutions to remove the boundaries of traditional television and make the world’s video content universally enjoyable by all viewers, on any device, across any network, at any time. Now in its second decade of developing market-leading video convergence solutions, Envivio has amassed dozens of patents, pioneered video-over-IP methods, and led in the deployment of emerging standards and new technologies.  Envivio’s customers include global tier-1 service providers, including eight of the top 10 mobile operators, seven of the top 10 broadband providers and three of the top four cable operators.  Envivio is headquartered in South San Francisco, California and has offices worldwide including France, England, China, Singapore and Japan.