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WebRTC encoded transform

The rtctransform event is fired at a worker's DedicatedWorkerGlobalScope object when an encoded video or audio frame has been queued for processing by a WebRTC Encoded Transform.

The event's transformer property returns a RTCRtpScriptTransformer that exposes the ReadableStream on which the frame is queued, and a WritableStream where the frame can be written to inject it back into the WebRTC pipeline.

This event is not cancellable and does not bubble.

Networking

Browser support

Feature Desktop Mobile
Chrome
Edge
Firefox
Safari
Chrome Android
Safari iOS
RTCEncodedAudioFrame
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rtctransform_event

The rtctransform event is fired at a worker's DedicatedWorkerGlobalScope object when an encoded video or audio frame has been queued for processing by a WebRTC API/Using Encoded Transforms.
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data

The data property of the RTCEncodedAudioFrame interface returns a buffer containing the data for an encoded frame.
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getMetadata

The getMetadata() method of the RTCEncodedAudioFrame interface returns an object containing the metadata associated with the frame.
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RTCEncodedAudioFrame

The RTCEncodedAudioFrame() constructor creates a new and fully independent RTCEncodedAudioFrame object.
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RTCEncodedVideoFrame

The RTCEncodedVideoFrame of the WebRTC API represents an encoded video frame in the WebRTC receiver or sender pipeline, which may be modified using a WebRTC Encoded Transform.
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data

The data property of the RTCEncodedVideoFrame interface returns a buffer containing the frame data.
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getMetadata

The getMetadata() method of the RTCEncodedVideoFrame interface returns an object containing the metadata associated with the frame.
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RTCEncodedVideoFrame

The RTCEncodedVideoFrame() constructor creates a new and fully independent RTCEncodedVideoFrame object.
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type

The type read-only property of the RTCEncodedVideoFrame interface indicates whether this frame is a key frame or a delta frame.
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transform

The transform property of the RTCRtpReceiver object is used to insert a transform stream (TransformStream) running in a worker thread into the receiver pipeline. This allows stream transforms to be applied to encoded video and audio frames as they arrive from the packetizer (before they are played/rendered).
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RTCRtpScriptTransform

The RTCRtpScriptTransform interface of the WebRTC API is used to insert a WebRTC Encoded Transform (a TransformStream running in a worker thread) into the WebRTC sender and receiver pipelines.
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RTCRtpScriptTransform

The RTCRtpScriptTransform() constructor creates a new RTCRtpScriptTransform object.
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RTCRtpScriptTransformer

The RTCRtpScriptTransformer interface of the WebRTC API provides a worker-side Stream API interface that a WebRTC Encoded Transform can use to modify encoded media frames in the incoming and outgoing WebRTC pipelines.
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generateKeyFrame

The generateKeyFrame() method of the RTCRtpScriptTransformer interface causes a video encoder to generate a key frame.
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options

The options read-only property of the RTCRtpScriptTransformer interface returns the object that was (optionally) passed as the second argument during construction of the corresponding RTCRtpScriptTransform.
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readable

The readable read-only property of the RTCRtpScriptTransformer interface returns a ReadableStream instance is a source for encoded media frames.
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sendKeyFrameRequest

The sendKeyFrameRequest() method of the RTCRtpScriptTransformer interface may be called by a WebRTC Encoded Transform that is processing incoming encoded video frames, in order to request a key frame from the sender.
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writable

The writable read-only property of the RTCRtpScriptTransformer interface returns a WritableStream instance that can be used as a sink for encoded media frames enqueued on the corresponding RTCRtpScriptTransformer.readable.
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transform

The transform property of the RTCRtpSender object is used to insert a transform stream (TransformStream) running in a worker thread into the sender pipeline. This allows stream transforms to be applied to encoded video and audio frames after they are output by a codec, and before they are sent.
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RTCTransformEvent

The RTCTransformEvent of the WebRTC API represent an event that is fired in a dedicated worker when an encoded frame has been queued for processing by a WebRTC Encoded Transform.
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transformer

The read-only transformer property of the RTCTransformEvent interface returns the RTCRtpScriptTransformer associated with the event.
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1+Supported (version) Not supported ※Has note Sub-feature descriptions sourced from MDN Web Docs (CC BY-SA 2.5)

Syntax

JAVASCRIPT 
addEventListener("rtctransform", (event) => { })

onrtctransform = (event) => { }

Use cases

  • Using WebRTC encoded transform

    The rtctransform event is fired at a worker's DedicatedWorkerGlobalScope object when an encoded video or audio frame has been queued for processing by a WebRTC Encoded Transform.

Cautions

  • May not be supported in older browsers.

Implementation notes

  • Some APIs require a secure context (HTTPS) or user activation. Check the requirements before use.

Related links