Trick-play track via I-frames
In an HLS output group, you can support a trick-play track by providing an I-frame-only manifest.
How the method works
When you create the HLS output group, you create one or more video outputs, in the usual way. In each video output, you enable the field to create an I-frame-only manifest that conforms to the HLS specification.
Elemental Live produces two child manifests for each encode (stream)—one manifest for handling the video in the usual way, and the I-frame-only manifest. The I-frame-only manifest lets the downstream player identify specific video frames to request, to construct the trick-play track. So this trick-play track method doesn't produce additional encodes in the output group.
Each I-frame-only manifest contains the following:
-
One
#EXT-X-I-FRAMES-ONLYtag, to indicate that the manifest is I-frame-only. -
Many
#EXT-X-BYTERANGEentries. Each entry identifies the position of an I-frame position.
Setting up
You set up the trick-play track once for the entire HLS output group.
Note
The information in this section assumes that you are familiar with the general steps for creating an event.
To set up an I-frame-only manifest
Include these steps when you create the HLS output group.
-
In the HLS Output Group, in HLS Outputs, choose Add Output to add an output. Or display an existing output.
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In the output, choose Advanced to open that section, then select Add I-frame Only Manifest.
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Set up the remaining fields in the output group as you normally would. Set up the video, audio, and captions outputs and encodes as you normally would.
