transcoder-form-publish-amf

Transcoder (Form, Publish and AMF) (transcoder-form-publish-amf)

This example extends transcoder-form-and-publish by adding AMF metadata send controls while the top-level stream is publishing.

It demonstrates sending metadata on the source stream so subscribers on transcoded variants can receive the same metadata signaling.

What This Example Demonstrates

• ABR provision submission to Stream Manager
• top-level source publish with WHIPClient and transcode: true
• AMF metadata send during active publish using publisher.send('onMetaData', ...)
• metadata propagation intent across all generated transcoded variants

Deployment Prerequisite

Requires Stream Manager with a transcoder node in the target node group.

As with the other transcoder examples, ladder outputs are generated from the top-level source variant and served adaptively by the platform.

End-to-End Flow

1. Submit ABR ladder form.
2. Start publishing the HIGH/source variant.
3. Use AMF form input to send metadata while live.
4. Subscribers on any generated variant can consume shared metadata events.

Minimal Developer Snippet

await postAbrProvisions(adminUsername, adminPassword, settings, provision)
await publisher.initWithStream(
  {
    endpoint,
    streamName: `${streamName}_1`,
    connectionParams: { ...connectionParams, transcode: true },
    mediaElementId: 'publisher-video',
  },
  previewStream
)
await publisher.publish()

// During active publish:
await publisher.send('onMetaData', { metadata: 'your metadata payload' })

AMF Controls in This Example

• AMF input and submit controls are disabled until publish starts.
• On Publish.Start, controls are enabled.
• On publish stop/failure, controls are disabled again.

This keeps metadata send behavior scoped to active source-stream publishing only.

Stream Manager Notes

• Stream Manager mode is required.
• Admin credentials are required for provision submission.
• This example combines provisioning, source publish, and metadata signaling in one flow.

Where to Look in This Example

• provision submit: onSubmit()
• source publish setup: startPublish()
• AMF send action: sendAmfMetadata()
• AMF form state control: syncAmfMetadataControls()
• publish lifecycle handling: onPublisherEvent()

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Use this example as the reference when your transcoded ladder workflows also require synchronized AMF metadata signaling to downstream subscribers.