Encoding in the Cloud
Range of Services
The first issue is the range of services provided, particularly as related to delivering your files to distribution partners. In particular, one significant question to ask is whether the service offers platform-specific encoding presets and whether it ensures that necessary metadata is intact and presented in the proper form.
For example, Encoding.com recently announced Brightcove Batch Provisioning Integration, a plug-in that "will automatically deliver the encoded video library to the Brightcove customer’s account (via the Brightcove FTP Batch Provisioning) along with the necessary metadata (media title, description, tags, etc.)." mPOINT offers metadata management and transformation features that include "metadata transformation for any destination" and the ability to create a "delivery partner metadata specification profile" for each target platform. HD Cloud has a Metadata Management Suite on its short-term product road map.
Metadata management is critical to delivering your file to the proper location and getting eyeballs after it’s posted. If this is a function that you expect your cloud encoding service to perform, make sure that the service supports your current and planned distribution platforms or at least has a sufficiently flexible programming interface so you can roll your own integration.
Also critical is how the system will integrate with your current content management system. All the services offer file upload and management APIs, so this really shouldn’t be an issue, but you should still have your CMS and tech folks looking at the API early in the evaluation process.
You should also examine alternatives for streamlining the video delivery process since that’s a significant bottleneck for many companies. For example, mPOINT supports pull and push ingest, as well as transfer via an Aspera client, which can boost transfer speeds by up to 1,000 times over standard FTP, according to Aspera’s literature.
Format Support
Whichever cloud encoding platform you choose, you don’t want to take a step backward in your encoding practices. In terms of general encoding parameters, while browsing the various encoding platforms, I noticed that some vendors don’t provide options for VBR and CBR or the ability to set the key frame interval.
With H.264, check to make sure that the vendor supports the baseline, main, and high profiles; enables CABAC support; and, at the very least, lets you set options such as the number of sequential B-frames between I- and P-frames.
When encoding for non-H.264 Flash applications, make sure that the vendor can produce using the VP6 codec rather than Sorenson Spark. VP6 encoding options should include the availability of VP6-E and VP6-S, as well as single- and dual-pass encoding.
Regarding Windows Media, if you’ve started tweaking Microsoft’s advanced encoding parameters by using applications such as Rhozet Carbon Coder, Inlet Fathom, or Microsoft Expression Encoder, or by using the WMV9 PowerToy or command line encoding, note that none of the cloud encoding services offer this level of control. In some circumstances, this could mean a drop in quality.
If you’re currently producing DVD or Blu-ray Discs, ask about support for MPEG-2, H.264, and VC-1 output. If you’re currently supporting any bitrate-switching schemes—whether multiple-bitrate files for Windows Media, Move Network’s Adaptive Stream, Smooth Streaming for Silverlight, or dynamic streaming for Flash—ask about any specific output requirements.