Input and output requirements
In order for MediaLive to lock pipelines, the following conditions must be in effect in the channel. When pipeline locking isn't possible, processing continues. As soon as the required conditions are again in effect, MediaLive starts to lock again.
No support for HLS inputs
The channel can't include HLS inputs.
If the channel includes an HLS input, MediaLive stops attempting to lock pipelines in the channel. Pipeline locking won't resume, even after the channel switches to another input.
Inputs must include embedded timecode (source timecode method)
When you use the source timecode pipeline locking method (the default), the input must include embedded timecode. These rules apply:
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When using the source timecode method, the input must have an embedded timecode. This requirement applies to both pipeline locking mode and epoch locking mode.
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For epoch-locking mode, the embedded timecode must be within 2 minutes of epoch time. If the timecode is off by more than 2 minutes, MediaLive considers that the source doesn't meet the requirements for pipeline locking.
MediaLive continually probes the current source for an embedded timecode. Whenever it doesn't detect the timecode, it temporarily suspends the attempt to lock pipelines.
Requirements for video aligned locking
Note
Video aligned locking is available only when the output locking mode is set to PIPELINE_LOCKING (not EPOCH_LOCKING).
When you use video aligned locking (Pipeline locking method set to VIDEO_ALIGNMENT), embedded timecodes are not required.
Input requirements
Certain input types are not compatible with video alignment:
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File inputs (MP4_FILE, TS_FILE)
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HLS inputs (URL_PULL with HLS content)
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RTMP_PULL inputs
When an incompatible input type is active, video aligned locking runs in "open loop" mode (unlocked) but continues processing. No validation error is raised, which supports input switching workflows where some inputs may be incompatible.
For all other input types, video aligned locking uses visual signature comparison to synchronize the pipelines. Both pipelines must receive the same video content for successful synchronization.
Frame rate requirements
The conversion between the input framerate (or framerates) and the desired output framerate must be simple, which means that one of these statements must apply:
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The output framerate must be a whole number multiple of the input framerate. For example, the input framerate might be 45 FPS, and the output framerate might be 90 FPS.
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The input framerate must be a whole number multiple of the output framerate. For example, the input framerate might be 60 FPS, and the output framerate might be 30 FPS.
MediaLive identifies the source input framerate when it switches to a new input, and determines if a simple conversion applies. If it doesn't, MediaLive stops the attempt to lock pipelines until the channel switches to the next input. Even if the source input framerate changes in mid source (so that a simple conversion applies), MediaLive doesn't start attempting to lock again.
Note that with these rules, it is possible for the framerates to be integers. For example, if the input framerate is 29.97 FPS and the output framerate is 59.94 FPS.
Following are examples of complex framerates. You can't use the input if one of these combinations applies to your channel:
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This isn't supported: Input FPS is 59.4, output FPS is 60.
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This isn't supported: Input FPS is 45, output FPS is 60.
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This isn't supported: Input FPS is 29.97 FPS, output FPS is 23.978.
Epoch locking and SCTE 35
There are constraints for using epoch locking in an HLS or MediaPackage output group.
HLS output group
It's not possible to enable SCTE 35 passthrough or manifest decoration in an HLS output group in a channel that uses epoch locking. You will get a validation error when you save the channel. You must decide how to resolve this conflict:
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Don't enable epoch locking in the entire channel: You can set the mode to regular pipeline locking in the entire channel, and keep SCTE 35 passthrough in the HLS output group.
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Disable SCTE 35 passthrough in the HLS output group: You can keep epoch locking but disable SCTE 35 passthrough and manifest decoration in the HLS output group. You can still enable SCTE 35 passthrough in other output groups.
MediaPackage output group
For a MediaPackage output group, constraints apply if the input includes SCTE 35 messages:
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When epoch locking isn't enabled in the channel, MediaLive automatically passes through any SCTE 35 messages from the input and automatically enables manifest decoration.
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When epoch locking is enabled, MediaLive automatically disables SCTE 35 passthrough and manifest decoration in the MediaPackage output group.
You should decide which feature you want to keep. You can keep the SCTE 35 messages (in which case you must disable epoch locking in the entire channel). Or you can enable epoch locking but lose passthrough of the SCTE 35 messages. Note that there is no advantage to setting up the output as an HLS output group, because similar constraints apply, as described above.
