March 4, 2015
By Jan Ozer Contributing Editor
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Buyer's Guide to Cloud-Based Video Encoding and Transcoding 2015

In general, the major SaaS vendors, Encoding.com and Zencoder, performed similarly in my trials. Amazon’s Elastic Transcoder took more than twice as long, making it a poor choice for companies requiring the absolute fastest encoding time. At the other end of the spectrum, QuickFire.TV was exceptionally fast, finishing all encoding in less than 20 percent of the time required by the second-fastest encoder.

Obviously, performance matters if you’re racing to publish time-sensitive content. On the other hand, for most other encoding chores, the difference between an encoding time of 20 minutes and 2 hours might not be that significant.

WHAT DOES IT COST?

Pricing model and cost are where you’ll find the most significant differences between the cloud offerings. Unfortunately, you’ll have to work very hard to gather useful comparative data on these points for multiple reasons. First, there’s a big difference in pricing between Elemental’s PaaS model, where price depends on reserved CPUs, and SaaS models that simply charge based on usage. Second, some SaaS providers charge by the encoding minute (Zencoder, Amazon) while others charge by GB in and out (Encoding.com, Heywatch).

Third, many vendors have individual pricing tweaks. For example, Zencoder charges 25 percent of the normal cost for files produced via transmuxing, so you would pay full price for MP4s, but only 25 percent of that price for the MP4s converted into HLS or HDS. Encoding.com offers some premium price levels for higher performance, and QuickFire.TV offers three pricing models based on encoding time and quality. All vendors adjust price based on monthly commitment, and if you’re big enough, I’m guessing most vendors would throw the price list out and negotiate from scratch.

To estimate pricing across the board, you’ll have to quantify the number of files you’ll encode each month, their duration, input size, output size, how quickly you’ll need the files, and how firmly you’re willing to commit to these quantities. You can get a long way using the price schedules most vendors supply, but to get information that you can rely on, you should verify the numbers with a sales rep.

TEST, TEST, TEST

Most cloud providers offer a reasonable number of test encodes, which you should use to ensure compatibility with your existing workflows. Compatibility shouldn’t be a problem, but you never know for sure unless you test.

Now let’s turn our attention to choosing a cloud encoder for live production.

Cloud Transcoding for Live

A live cloud transcoder inputs a single live signal and transcodes that signal into multiple files. So, you might transmit a single 720p, 5Mbps stream into the cloud, which the transcoder converts to six separate streams for adaptive delivery. After transcoding, the cloud transcoder can transmux the streams into different container formats for delivery to multiple platforms, such as HTTP Live Streaming (HLS) for iOS devices, and HTTP Dynamic Streaming (HDS) for delivery to Flash-based desktops and notebooks.

Live cloud transcoding has two key benefits. First, because you’re only creating a single stream onsite, you can use a very inexpensive live encoder. Second, again because you’re only sending a single stream to the cloud for transcoding, your outbound bandwidth requirements are minimal. With live cloud transcoding, you can provide an adaptive live experience where it wouldn’t be possible if you were encoding onsite. These two benefits make live cloud transcoding beneficial to virtually all live event producers who haven’t already invested in an expensive multiple stream encoder and the bandwidth necessary to push the encoded streams into the cloud.

START WITH A LIST, AGAIN

As you would expect, most of the relevant questions asked of live encoder candidates are similar, if not identical, to those you would ask to a VOD provider. Start with a list of required formats and input and output points, and make sure the live service provider can check all the relevant boxes. Ditto for DRM, captions, and other extras. If your existing on-prem or VOD cloud provider has a live service offering, check that out as well; it’s usually simplest to work with one company than two.

You have the same roll-your-own option as described above with the Wowza Transcoder, which you can deploy on a variety of cloud platforms, including Amazon EC2, Rackspace, and Microsoft Azure. You can also choose from among several SaaS providers, most notably Zencoder, which was among the first in the space, and Elemental, which was one of the first appliance vendors to move to the cloud.

Interfaces vary by service provider; some are scripting only, while others offer a traditional user interface. As with VOD cloud encoders, be sure to choose a provider with an interface that matches your technical capabilities.

While I haven’t tested live transcoding quality, I would expect it to be relatively uniform among the service providers for reasons described above. Performance should not be an issue; the providers can either create the required number of streams or not. Pricing varies among the various providers, though there’s a great deal more uniformity than with VOD providers.

SERVICE IS THE THING

Service is a huge differentiator, since if your live transcoder fails, so does your event. Make sure the provider offers live telephone support during the hours you’ll be broadcasting, determine what it costs, and ask if there are any service-related guarantees. I would also check if the provider offers a free test broadcast; if not, produce a test anyway. You never should go live with a new provider on a mission-critical event without completing a live run-through first.

This article appears in the 2015 Streaming Media Sourcebook as "Cloud-Based Video Encoding and Transcoding."