Implementing pipeline locking
You can configure MediaLive to use pipeline locking to synchronize outputs. Pipeline locking works with standard channels (which have two pipelines) and with single-pipeline channels using linked channels. Pipeline locking ensures that the outputs are frame-accurate with each other. Pipeline locking is enabled by default.
When pipeline locking is enabled. MediaLive locks the pipelines on a best-efforts basis. When pipeline locking isn't possible, processing continues. The inability to lock pipelines isn't considered to be a fault condition.
The default mode for pipeling locking is pipeline locking You can't disable pipeline locking in the applicable output types. But you should configure the behavior, to make sure it suits your workflow.
Note
You might be familiar with the term output locking. In MediaLive, the term used is pipeline locking. Whatever term is used, the effect is identical: frame accurate outputs.
Pipeline locking modes
There are two output locking modes:
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Pipeline locking (the default): lock the two pipelines to each other
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Epoch locking: lock the pipelines using the Unix epoch as the reference.
Pipeline locking methods
When you use pipeline locking mode, you can choose the method that MediaLive uses to synchronize the pipelines:
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Source timecode (the default): MediaLive uses embedded timecodes from the input source to synchronize the pipelines. This method works best with reliable timecodes.
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Video alignment: MediaLive uses visual signature comparison between encoders to synchronize the pipelines. This method does not require embedded timecodes and is useful when your input sources lack timecodes or have unreliable timecodes. For more information, see Requirements for video aligned locking.
Applicable outputs
Source timecode pipeline locking applies only to the following types of outputs:
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HLS (Live mode)
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MediaPackage
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CMAF Ingest
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Microsoft Smooth
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UDP outputs that are segmented. You might have configured a UDP output group for segmented outputs. To verify, in a UDP output group, choose Output then Network Settings, then Container Settings. Look for the three fields that start with the term Segmentation.
Video aligned locking applies only to the following types of outputs:
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HLS (Live mode)
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CMAF Ingest
The channel can contain other types of outputs, but MediaLive won't attempt to lock their outputs. This means that in those other output groups, there is no guarantee that the content of the two pipelines will be frame-accurate with each other.
