Auxiliary

Name	Description
on()	Attaches an event handler function for a built-in event.
off()	Removes an event handler.
offAll()	Removes all event handlers from the specified event. If no event is specified, remove all event handlers.
dispose()	Releases all resources used by the CameraEnhancer instance.
disposed	A readonly boolean value indicating whether the CameraEnhancer instance has been disposed.
getVersion()	Returns the version of the library.
detectEnvironment()	Returns a report on the current running environments.

Type definition used on this page:

type EventName = "cameraChange" | "cameraOpen" | "cameraClose" | "resolutionChange" | "played" | "singleFrameAcquired" | "frameAddedToBuffer";

Built-in Event Reference Table

Event Name	Description
cameraChange	Triggered when a different camera is used.
cameraOpen	Triggered when the camera opens.
cameraClose	Triggered when the camera closes.
resolutionChange	Triggered when the resolution changes.
played	Triggered when the video starts playing/streaming.
singleFrameAcquired	Triggered when an image is acquired under the single-frame mode.
frameAddedToBuffer	Triggered each time a new frame is added to the buffer.

on

Attaches an event handler function for a built-in event.

on(eventName: EventName, listener: Function): void;

Parameters

eventName: specifies the event.

listener: specifies the handler function.

Return value

None.

Code Snippet

let enhancer = await Dynamsoft.DCE.CameraEnhancer.createInstance();
enhancer.on("cameraChange", playCallBackInfo => {
    console.log(playCallBackInfo.deviceId);
});
enhancer.on("cameraOpen", playCallBackInfo => {
    console.log(playCallBackInfo.deviceId);
});
enhancer.on("cameraClose", playCallBackInfo => {
    console.log(playCallBackInfo.deviceId);
});
enhancer.on("resolutionChange", playCallBackInfo => {
    console.log("width:" + playCallBackInfo.width);
    console.log("height:" + playCallBackInfo.height);
});
enhancer.on("played", playCallBackInfo => {
    console.log(playCallBackInfo.deviceId);
});
enhancer.on("singleFrameAcquired", dceFrame => {
    document.body.appendChild(dceFrame.toCanvas());
});
enhancer.on("frameAddedToBuffer", () => {
    let dceFrame = enhancer.getFrameFromBuffer();
    document.body.appendChild(dceFrame.toCanvas());
});

off

Removes an event handler.

off(eventName: EventName, listener: Function): void;

Parameters

eventName: specifies the event.

listener: specifies the handler function.

Return value

None.

Code Snippet

let enhancer = await Dynamsoft.DCE.CameraEnhancer.createInstance();
let cameraChanged = playCallBackInfo => {
    console.log(playCallBackInfo.deviceId);
    enhancer.off("cameraChange", cameraChanged);
}
enhancer.on("cameraChange", cameraChanged);

offAll

Removes all event handlers from the specified event. If no event is specified, remove all event handlers.

offAll(eventName?: EventName): void;

Parameters

eventName: specifies the event.

Return value

None.

Code Snippet

enhancer.offAll("cameraChange");

dispose

Releases all resources used by the CameraEnhancer instance. After that, the instance will be left with only the property disposed (the value is true).

The HTML elements used by the instance’s UI element are only removed when removeUIElement is set to true. Otherwise, they are only hidden.

dispose(removeUIElement?: boolean): void;

Parameters

removeUIElement: whether to hide or remove the HTML elements in the instance’s UI element.

Return value

None.

Code Snippet

let enhancer = await Dynamsoft.DCE.CameraEnhancer.createInstance();
// Use the object to perform some tasks
enhancer.dispose();

disposed

A readonly boolean value indicating whether the CameraEnhancer instance has been disposed.

This property replaces the deprecated old property isDisposed.

readonly disposed: boolean; 

Code Snippet

let enhancer = await Dynamsoft.DCE.CameraEnhancer.createInstance();
//...
let flag = enhancer.disposed;

getVersion

Returns the version of the library.

static getVersion(): string;

Parameters

None.

Return value

The version string of the library.

Code Snippet

Dynamsoft.DCE.CameraEnhancer.getVersion();

detectEnvironment

Returns a report (in JSON) on the current running environments.

static detectEnvironment(): Promise<any>;

Parameters

None.

Return value

A JSON object about the running environment. For example

{
    "wasm": true,
    "worker": true,
    "getUserMedia": true,
    "camera": true,
    "browser": "Chrome",
    "version": 90,
    "OS": "Windows"
}

Code Snippet

await Dynamsoft.DCE.CameraEnhancer.detectEnvironment();