Having observed the evolution in both claims and the actuals of how mobile video is optimized during my years in product development at Cisco, and in my role as Senior Director of Optimization Products at Skyfire, I've also observed the maturation of video optimization techniques. I've come to see just how robust optimization solutions can be when much of the processing capability is moved to the cloud, and the benefit that provides for both operators and their consumers. Full Transcoding, the technique used by Skyfire, is far superior and more flexible than traditional solutions. I thought I'd explain why.
Most optimization vendors who provide video optimization provide it via what is called “transrating”, or a very basic form of transcoding. In a nutshell, transrating allows limited bitrate and/or frame rate reductions on a video through the use of “requantization” techniques. Transrating is computationally simple, but it does not allow either (a) change in video codec or (b) change in resolution. Transrated video also results in spatial and temporal “drift”, which is basically accumulation of errors over the course of multiple frames that leads to degradation in video quality. Transrating generally provides at most 25% to 30% savings; beyond that, severe artifacting will destroy video quality.
Full Transcoding is a far more flexible technique. It allows any given video to be converted to a different video codec and a different resolution. Transcoding works by decoding, and then re- encoding the video. Because transcoding does not result in spatial or temporal drift, and provides full flexibility in choosing optimal encoding parameters, it can provide a much higher boost in bandwidth capacity to an operator – up to around 60% -- without major impact to video quality.
So why don't legacy inline appliance vendors move to this model? Well, traditional inline appliances are limited in CPU processing capacity, and simply do not have the horsepower for transcoding. By harnessing the cloud, Skyfire’s solution makes massive transcoding capacity available at low cost, shared between regions. Because of the higher efficiency, far superior transcoding techniques can be deployed at a similar cost as that of simple transrating solutions – and additional optimization resources can be very rapidly deployed in cases of very sudden shifts in network utilization (for instance, massive demand on the operator network following the sudden death of a major political figure or celebrity).
This convergence of mobile, video, and cloud technologies is providing a consumer experience and optimization savings that previously couldn’t even be dreamed of. We've seen here at Skyfire that our flexible cloud architecture and intelligent traffic steering dramatically reduces an operator’s total cost of ownership vs. the cost of legacy in-line solutions. Full transcoding in the cloud is just the start. The mobile internet will never be the same again.