transcoder-form-and-publish

Transcoder (Form and Publish) (transcoder-form-and-publish)

This example extends transcoder-form-only by adding publisher workflow after provisioning.

You first submit ABR provisions to Stream Manager, then publish the top-level variant stream so the transcoder can generate the remaining ladder variants.

What This Example Demonstrates

• ABR provision submission (HIGH/MID/LOW variants)
• previewing and publishing the top-level stream (_1) with WHIPClient
• sending publish connectionParams.transcode: true to engage transcoder flow
• publishing the source stream that drives generated variant outputs

Deployment Prerequisite

Requires Stream Manager deployment with an available transcoder node in the target node group.

The transcoder generates lower variants from the high/source variant. Subscriber delivery across the ladder is then managed server-side according to client network conditions.

End-to-End Flow

1. Submit ABR ladder form.
2. Example creates preview using requested HIGH tier width/height.
3. Start publish on the HIGH stream GUID (<app>/<stream>_1).
4. Transcoder receives source stream and produces additional ladder variants (_2, _3).
5. Subscribers can consume the appropriate variant endpoint/path for their conditions.

Minimal Developer Snippet

await postAbrProvisions(adminUsername, adminPassword, settings, provision)

const highStreamName = `${streamName}_1`
const endpoint = resolveEndpointFromSettings({ ...settings, streamName: highStreamName }, 'whip')

await publisher.initWithStream(
  {
    endpoint,
    streamName: highStreamName,
    mediaElementId: 'publisher-video',
    connectionParams: {
      ...connectionParams,
      transcode: true,
    },
  },
  previewStream
)
await publisher.publish()

Practical Notes

• Stream Manager + credentials are required.
• This example is focused on provisioning + source publish.
• Variant playback verification is done in subscriber workflows targeting provisioned stream GUIDs.

Where to Look in This Example

• ABR form parsing/provision: collectAbrProvisions() and onSubmit()
• preview setup from HIGH tier: setupPublisherPreview()
• publish flow: startPublish()
• unpublish flow: stopPublish()
• event/status handling: onPublisherEvent()

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Pair this with transcoder-form-publish-amf to extend the same flow with AMF metadata delivery across transcoded variants.