About Amazon Elastic Transcoder
Amazon Elastic Transcoder is an Amazon web service that provides on-demand transcoding of media files between all commonly used audio and video formats. Once the Video plug-in has been correctly configured, it is largely invisible to plug-in users, simply providing a background service. Two Elastic Transcoder concepts will, however, often be visible: when publishing a media file, the user will usually be able to choose between different pipelines and preset groups:
A pipeline is simply an Elastic Transcoder job queue. In a typical set-up there are two pipelines, one for normal jobs and one for high priority jobs, and the Content Studio user can choose which to use when publishing a media content item. There is no actual difference between the two pipelines other than their name, so the high priority pipeline will only work as a "fast lane" if it is actually reserved for a small number of high priority jobs. Pipelines are defined in Elastic Transcoder.
A preset is a set of parameters defining in great detail the output required from a transcoding job. For a video transcoding, it defines the file container format, video and audio codecs, bit rate, frame rate, width and height and so on. Presets are defined in Elastic Transcoder. A preset group is a named group of presets defined during the configuration of the Video plug-in. The idea is that a preset group should contain all the presets required to publish a particular type of media file in a particular context. Typically, a user will only need to choose between a small number of preset groups ("Standard Video" and "High Res Video", for example) and in some cases may not need to choose at all, since only one preset group has been defined.
The pipelines and preset groups available to the Video plug-in are defined in XML files called transcoder configuration files. Several of these files may be defined in order to provide different set-ups for different publications. For further information, see Transcoder Configuration Files.