The global online-video market will be worth US$37 billion by 2017, driven by the popularity of services like Netflix and YouTube.

Latest forecasts from Informa Telecoms & Media says the figure is made up of the three key video-revenue streams of advertising, subscriptions and transactions.

But despite the market maturing, Informa believes advertising will continue to be a larger revenue generator than subscriptions in 2017, as it is in 2012.

“It’s clear that online video, today, is worth much more than the digital cents and dimes of yore, and is attracting real, and growing, revenues," says Giles Cottle, principal analyst and author of “OTT Video Revenue Forecasts”.

"But this value is concentrated around a select few players.

"We estimate that Apple, Google, Netflix and the global broadcasters (including Hulu), combined, account for about 70% of all online video revenue today– so if you aren’t one of these players, then the chances are you aren’t making a great deal of money from online delivery today”.

Online video remains a small, but growing, proportion of total TV and video revenues according to Informa, who estimate it will account for 8% of such revenues by 2017

By the end of the decade, if current growth rates continue, it will account for over 10% of revenues with its value in the market today concentrated among only a few players.

“The big change to the OTT revenue mix will come when operators start to offer not just low-cost online services, like Sky’s Now TV, but stand-alone online versions of their services that come close, in terms of content availability and price, to their core Pay TV services today," Cottle says.

"Even very modest take-up of these services will completely distort the online video market."

US dominance of the global market is expected to wane over the next five years, but the country will still contribute over half of all revenues by 2017.

The US accounts for approximately 75% of revenues today, but that will drop to less than 60% in 2017 as Europe and Asia grow more quickly according to the report.