Smelter

import Smelter from "@swmansion/smelter-web-wasm"

Smelter class is a primary way of interacting with the Smelter server.

Usage

To use Smelter follow this life cycle:

• Create instance new Smelter().
• Call await smelter.init().
• (optional) Register inputs, outputs or other resources.
• Call await smelter.start().
• (optional) Register inputs, outputs or other resources.
• At the end, call await smelter.terminate()

new Smelter()

Creates a new Smelter instance. You have to call init() first before this object can be used.

new Smelter(options: SmelterOptions)

Type definitions

  type Framerate = { num: number; den: number; };
  type SmelterOptions = {
    framerate?: Framerate | number;
    streamFallbackTimeoutMs: number;
  };

init()

smelter.init(): Promise<void>

Initialize the Smelter instance.

After init() you can start connecting inputs/outputs or register other elements. However, no output stream will be produced until start() method is called.

start()

smelter.start(): Promise<void>

Starts the processing pipeline. Any previously registered output will start producing the video/audio stream.

registerOutput()

smelter.registerOutput(
    outputId: string,
    output: RegisterOutput,
): Promise<object>

Type definitions

export type RegisterOutput =
    | {
        type: 'stream';
        video: {
          resolution: Api.Resolution;
        };
        audio?: boolean;
      }
    | {
        type: 'canvas';
        video: {
          canvas: HTMLCanvasElement;
          resolution: Api.Resolution;
        };
        audio?: boolean;
      }
    | {
        type: 'whip_client';
        endpointUrl: string;
        bearerToken?: string;
        iceServers?: RTCConfiguration['iceServers'];
        video: {
          resolution: Api.Resolution;
          maxBitrate?: number;
        };
        audio?: boolean;
      };

Register external destination that can be used as a smelter output. Visit output documentation to learn more.

• Canvas (Web API)
• MediaStream (Web API)
• WHIP (Web API)

unregisterOutput()

smelter.unregisterOutput(outputId: string): Promise<void>

Unregister previously registered output.

registerInput()

smelter.registerInput(
    inputId: string,
    input: RegisterInput
): Promise<object>

Type definitions

type RegisterInput =
    | { type: 'mp4'; url: string }
    | { type: 'camera' }
    | { type: 'screen_capture' }
    | { type: 'stream'; stream: MediaStream }
    | { type: 'whep_client'; endpointUrl: string; bearerToken?: string };

Register external source that can be used as a smelter input. Visit input documentation to learn more.

• Camera (Web API)
• Screen capture (Web API)
• MediaStream (Web API)
• MP4
• WHEP (Web API)

unregisterInput()

smelter.unregisterInput(inputId: string): Promise<void>

Unregister previously registered input.

registerImage()

import { Renderers } from "@swmansion/smelter"

smelter.registerImage(
    imageId: string,
    image: Renderers.RegisterImage,
): Promise<void>

Register an image asset. See RegisterImage to learn more.

unregisterImage()

smelter.unregisterImage(imageId: string): Promise<void>

Unregister a previously registered image asset.

registerShader()

import { Renderers } from "@swmnasion/smelter"

smelter.registerShader(
    shaderId: string,
    shader: Renderers.RegisterShader,
): Promise<void>

Register a shader. See RegisterShader to learn more.

unregisterShader()

smelter.unregisterShader(shaderId: string): Promise<void>

Unregister a previously registered shader.

registerFont()

smelter.registerFont(source: FontSource): Promise<void>

Type definitions

type FontSource = 'string' // URL

Register new font.

terminate()

smelter.terminate(): Promise<void>

Terminate the compositor instance.