Info Changing the way we consume media -
Changing the way we consume media
There is now a major – and arguably overdue - move towards faster broadband speeds around the world (writes Are Olafsen, Marketing Director of Digital Headends at Thomson). Political bodies are throwing their weight behind it: in Germany, for example, Chancellor Angela Merkel herself hosted a meeting at which she pressed for universal VSDL within ten years.
At the same time, we are making better use of the bandwidth we have. MPEG-4 offers significantly better compression efficiency. Given enough processing power in both the encoder and decoder, you can deliver good quality, jitter-free video over today’s broadband circuits. That is important. It means that the public at large will find viewing quality acceptable, even when watching longer content as streamed video.
The big name broadcasters offering catch-up and TV anytime services are bringing in a broad range of users to Internet television. All this is inevitably distorting the existing advertising revenue models. Advertisers are attracted by the tight editorial controls which streaming offers them. Commercial television worked by selling a bundle of slots across a schedule: on the Internet, advertisers expect to know precisely which content their commercial will be paired with. We have already considered the different advertising needs for online viewers. So there has to be a different playlist for each output platform: television cannot just be simulcast across television, online and mobile.
Similarly, graphics have to be tailored to the platform: logos and crawlers which are fine in high-definition television will not work in an online window, and will certainly not be appropriate on a handheld device. A “create once, publish everywhere” model becomes increasingly important to reduce the time-to-air and to consolidating multiple production steps into an integrated workflow. Easy handling of metadata during pre-production to automate segmenting, categorising, transcoding and publishing to alternate mediums.
All this means that the playout and headend requirements for multi-platform delivery are much more complex than might be thought. News and sport, two of the most important subjects for video content in terms of audience numbers, have quite differing needs in terms of viewing expectations. In addition they need to be adapted to suit the type of device on which they are being watched. Live sport is, of course, live sport, but a picture that looks great on a large high definition screen may not work online and will certainly not be appropriate for mobile devices.
A set of image analysis algorithms, which model the performance of the human eye, determines (in real time) where the principal zone of interest lies in the image. This can be used to zoom into a part of the picture to create a framing which is much more relevant to different screens, and it can be used to drive the compression engine to ensure that the important parts of the picture get the most bits.
Simply changing the resolution of the video is not enough. Coverage of the game might look great in HD, but shrink it down to a handheld mobile screen and the ball disappears.
Ultimately these advances will be linked with scalable video coding (SVC). This takes a layered approach to resolution, splitting the picture into a base layer at low resolution (and therefore very low bitrate) to which can be added further layers for more detail as the delivery capacity allows.
Standards for SVC are now being codified, allowing the headend and the receiving device to work together to sense the right bandwidth for the available network and thereby achieve the best quality possible. At IBC in 2008 Thomson demonstrated SVC in a live encoder, sending the same content to a range of devices including mobile handsets. Real world services could be online as early as 2010.
In conclusion, then, improved broadband speeds make high quality video streaming practical, and a pleasant experience for the typical viewer. In conjunction with improved compression and network management standards like the MPEG-4 codec, SVC bandwidth control and other initiatives like clock jitter elimination, bigger bitrates mean even higher quality and more simultaneous services.
For content providers, and particularly existing broadcasters, the challenge is to find ways of delivering media which is tailored to the platform aesthetically as well as technically, in a cost effective framework, within a realistic business model which attracts revenues as well as reinforcing the broadcast brand.