VideoPlugin

Generic video plugin

VideoPlugin is a specialization of a Plugin for VideoRenderer. Usually they perform simple 2D drawing tasks on a video canvas (for example, simplest face effects or adding debug information / graphics). VideoPlugin gets access to 2d canvas of VideoRenderer in load() and draws on this canvas directly in update(), on top of video frame using provided processing data.

Extends

• Plugin<ResultT>

Type Parameters

• ResultT extends object = object

Type of processing results

Constructors

new VideoPlugin()

new VideoPlugin<ResultT>(): VideoPlugin<ResultT>

Constructor

Returns

VideoPlugin<ResultT>

Overrides

Plugin.constructor

Properties

loaded

loaded: boolean = false

Loaded state

Inherited from

Plugin.loaded

---

ordinal

ordinal: number = PluginOrdinal.Render

Ordinal number

Inherited from

Plugin.ordinal

---

renderer?

protected optional renderer: Renderer<ResultT>

Renderer loaded the plugin

Inherited from

Plugin.renderer

---

videoCtx?

protected optional videoCtx: CanvasRenderingContext2D

Drawing context of video canvas layer

Methods

dispose()

dispose(): void

Dispose video plugin

Returns

void

Inherited from

Plugin.dispose

---

load()

load(renderer): Promise<void>

Initialize plugin

Initializes everything required for image drawing. Acquires video canvas 2d context of the renderer.

Parameters

• renderer: Renderer<ResultT>

Renderer this plugin is attached to

Returns

Promise<void>

Promise resolving when initialization is finished

Overrides

Plugin.load

---

setupCamera()

setupCamera(ratio, angle): void

Set camera parameters

Could be overridden to adjust plugin’s pipeline.

Parameters

• ratio: number

Aspect ration of input video

• angle: number

Vertical field of view in radians

Returns

void

Inherited from

Plugin.setupCamera

---

setupVideo()

setupVideo(size): void

Set video size

Could be overridden to adjust plugin’s pipeline.

Parameters

• size: Size

Resolution of input video

Returns

void

Inherited from

Plugin.setupVideo

---

unload()

unload(): void

Reset plugin

Releases all resources allocated in load(). Deletes the reference to 2d canvas context.

Returns

void

Overrides

Plugin.unload

---

update()

update(result, stream): Promise<void>

Update

Main method implementing the logic of the plugin. Overridden by derived classes for particular task.

Parameters

• result: ResultT

Results of video processing

• stream: HTMLCanvasElement

Captured video frame

Returns

Promise<void>

Promise resolving when update is finished

Inherited from

Plugin.update