CameraEnhancer - Auxiliary

Type definition used on this page:

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

Built-in Event Reference Table

NOTE:

When the event “singleFrameAcquired” is triggered, the acquired image data will be returned as a reference, not a copy. Therefore, any changes to it will change the data source, and if another callback returns the same image data, the modifications will be synchronized.

on

Registers an event listener for specific camera-related events.

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

Parameters

eventName: the name of the event to listen for. Possible values include “cameraOpen”, “cameraClose”, “cameraChange”, “resolutionChange”, “played”, “singleFrameAcquired”, and “frameAddedToBuffer”.

listener: the callback function to be invoked when the event occurs.

Return value

None.

Code Snippet

let cameraEnhancer = await Dynamsoft.DCE.CameraEnhancer.createInstance();
cameraEnhancer.on("cameraOpen", () => {
    console.log("Camera opened.");
});
cameraEnhancer.on("cameraClose", () => {
    console.log("Camera closed.");
});
cameraEnhancer.on("cameraChange", (deviceId, previousDeviceId) => {
    console.log("Camera changed.");
});
cameraEnhancer.on("resolutionChange", (resolution, previousResolution) => {
    console.log("Resolution changed.");
});
cameraEnhancer.on("played", () => {
    console.log("Video stream started.");
});
cameraEnhancer.on("singleFrameAcquired", dceFrame => {
    console.log("An image is acquired under the single-frame mode.");
});
cameraEnhancer.on("frameAddedToBuffer", () => {
    console.log("A new frame is added to the buffer.");
});

off

Removes an event listener previously registered with the on method.

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

Parameters

eventName: the name of the event to listen for. Possible values include “cameraOpen”, “cameraClose”, “cameraChange”, “resolutionChange”, “played”, “singleFrameAcquired”, and “frameAddedToBuffer”.

listener: the callback function to be invoked when the event occurs.

Return value

None.

Code Snippet

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