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Counting Cores by Bob Pank O nce again BVE hosted its one-day Cloud seminar. The new ExCel location meant that the room was away from the show floor and ideal for concentrating on the words flowing from the experts. Full- on attention was needed as squeezing in nine sessions between 10.00 and 17.45 meant that each would be short, sharp and to the point, which was certainly the case for the two I attended. First to catch my eye was ‘How can HPC be delivered through the cloud?’ moderated by Roland Brown of AndCubed. High performance computing is, of course, widely used in the post production industry which, in the UK, is centred on Soho. But it was an eye-opener to learn the scale of these operations, the challenges it produces and how the cloud can help. It was immediately clear that any cloud use is always to lower costs – no surprise there. The other point that came up several times was security; there still seems to be some worry there. It appears that Soho locations cannot always easily get all the electrical power and cooling needed to support sufficient computing power to produce results fast enough in-house. Considering the speed and efficiency of modern processors, this was quite a surprise to me. While the TV industry now firmly into HD (nearly 2K) and taking a serious look at 4K, the movie business already widely uses 2K and starting to look at 4K. The latter may not just represent a quadrupling of picture area, and the computer power needed to render an image. Roland Brown pointed out that many experts are of the opinion that bigger pictures may well need higher frame rates. This was recently used as an experiment in The Hobbit movie (48 f/s), and it is thought maybe necessary for 4K TV sports coverage. For a movie, that means eight times the computations of 2K (24 f/s). Rates if 120 f/s are talked about for 8K. So what does this have to do with the cloud? At the post production house the computations are executed by the ‘cores’, as FrameStore’s CTO Steve MacPherson pointed out. The company’s recent work on ‘Gravity’ required more than the 12,500 cores that were available in house. Adding more to cover this peak load over a two-month period proved not to be the most efficient solution. Negotiations with neighbouring post houses quickly solved the problem adding an extra temporally spare 2,000 cores made up the difference. The cores did not move but were accessed via the Internet. “ The other point that came up several times was security; there still seems to be some worry there” These ran 24/7 over the two months and created an HPC cloud. MacPherson said that “We can use the cloud only where it makes sense.” With the wealth of post companies in the Soho community there is plenty of potential for sharing cores, which is a benefit to all involved parties. Chris Johns, Chief Engineer BskyB, presented a broadcaster’s perspective of the cloud in which he identified the need for transcoding – an operation that has rapidly expanded with the proliferation of pads, pods, smart phones and other viewers. Apparently FOX has identified a requirement for 31 different formats to be delivered from the master. As the coding schemes tend to be asymmetric, with one necessarily complex coder that allows simpler decoding in the many viewing devices, coding takes a lot of computer power but can be run live. However, the computer power increase to code HD verses SD is not just the difference of pixels (about 5:1) but is also multiplied by the complexity of the of coding; H.264 verses MPEG- 2... and next up, HEVC will require another level of power. The cloud also adds a new degree of freedom. Mr Johns mentioned that BskyB’s very efficient production centre at Osterley is now running on limits of heat (a restriction that is also affecting many in the Soho community). He advises, “reinventing your green credentials” and so “off-line use outside is good... provided you have the bandwidth.” However he also urges caution, as sometimes it can be quicker to send a disc rather than using bandwidth. Harry Stover, Chief Enterprise Architect, BBC compared the broadcaster’s statistics with the cloud, such as the 250 billion (if I counted all the 0’s correctly) TV frames it produces per year, and tape storage at 20p/GB against the much higher cost of cloud storage. He also pointed out that no cloud provider offers tape storage. A single one-hour programme may comprise 1.3TB of data and that is probably a million times the size of the normal cloud object. These and more statistics clearly proved that there are big differences between what a big broadcaster needs and what the cloud can offer. Which then means you must make absolutely sure that your cloud provider really does understand exactly what performance you need. Stover also pointed out a one-off need arising from the immanent closedown of the BBC Television Centre. At which 42 | TV-BAY MAGAZINE TV-BAY075MAR13.indd 42 11/03/2013 16:51