There is no telling where VOD customers will view content; it could be anywhere from a home theatre in a dedicated projection room, an LED panel in the living room, a laptop in the office or more likely these days on a tablet or phone during a morning commute. One thing is certain though, as the resolution and dynamic range of these displays continues to increase across all of these devices, more efficient encoding methods are being employed to try and keep the transcoding requirements for all these devices under control.
Cable networks, CDNs and streaming content providers seem to face insurmountable challenges when optimizing their existing VOD asset libraries and trying to turn around new content to meet their delivery service level agreements (SLAs). A full-length 4K HDR feature could take traditional workflow infrastructures over a day to render out all of the adaptive bitrate (ABR) stacks required for the myriad of consumer players available today. However, with the ubiquity of cloud processing and the advent of new technologies such as AWS Elemental MediaConvert’s Accelerated Transcoding, these compute-heavy workflows can be processed with drastically reduced turnaround times, allowing customers to meet studio’s SLAs for transcode and QA with time to spare.
At its core, accelerated transcoding builds on parallel processing concepts like split and stitch, where media is broken down into segments for processing. However, this can be a tricky business, and if it isn’t done properly you can get spikes in data rates that can be problematic with different players. Accelerated transcoding is based on incredibly powerful engineering that takes into account data rates, analyzes types of GOP structures, player compatibility and can output a full gamut of codecs, including mezzanine file types like ProRes and XDCam. New engineering developments in transcoding combined with the power and price performance flexibility thanks to millions of computing cores in the cloud is truly changing the game for VOD workflows.
In practice, whenever a content distributor buys rights from a content owner they want to turn that content around and make it available to their customers as soon as possible. If it takes the content distributor a day to perform the transcoding, and then even more time for quality control (QC), they may lose a substantial percentage of VOD customers to their competition. Ideally, once a network secures a new piece of media from a content owner, they want the file transcoded, QC’d and available for customers on demand as soon as possible, within hours not weeks.
Accelerated transcoding is a very real solution that solves these complex compute heavy workflows. Not only is the transcode sped up by an order of magnitude, but thanks to a combination of new encoding technologies like quality-defined variable bitrate (QVBR), one transcode job can produce the whole ABR stack of 60-70 different deliverables with up to a 50% reduction of file size. The CDN cost savings alone are enough to make VOD catalogue owners evaluate the benefits of re-encoding their content libraries to take advantage of these new processes—especially now, when quality, price and speed are no longer obstacles.
Dan Germain is the senior product manager, Compression & VOD, for Amazon Web Services.
