Class DCVBarcodeReader

DCVBarcodeReader accesses the camera via a DCVCameraView object at the native level, then perform continuous barcode scanning on the incoming frames.

class DCVBarcodeReader

Method	Description
`createInstance`	Create an instance of `DCVBarcodeReader`.
`initLicense`	Initialize the license of Dynamsoft Barcode Reader.
`getVersion`	Get the version of `DCVBarcodeReader`, which is packaged in Dynamsoft Capture Vision.
`getRuntimeSettings`	Get the current runtime settings of `DCVBarcodeReader`.
`updateRuntimeSettings`	Update the runtime settings of `DCVBarcodeReader` with a DBRRuntimeSettings object, a preset template or a JSON String.
`resetRuntimeSettings`	Reset the runtime settings of `DCVBarcodeReader` to default.
`outputRuntimeSettingsToString`	Output the runtime settings of `DCVBarcodeReader` to string.
`startScanning`	Start the barcode decoding thread.
`stopScanning`	Stop the barcode decoding thread.
`addResultListener`	Specifies an event handler that fires after the library finishes scanning a frame.

createInstance

Create an instance of DCVBarcodeReader.

static createInstance(): Promise<DCVBarcodeReader>;

Return Value

An instance of DCVBarcodeReader.

Code Snippet

dbr = await Dynamsoft.DCVBarcodeReader.createInstance()

initLicense

Initialize the license of the Barcode Reader module.

static initLicense(license: String): Promise<void>;  

Parameters

license: A license key.

Code Snippet

try {
    await Dynamsoft.DCVBarcodeReader.initLicense("DLS2eyJvcmdhbml6YXRpb25JRCI6IjIwMDAwMSJ9");
} catch (e) {
    console.log(e)
}

getVersion

Get the version of DCVBarcodeReader, which is packaged in Dynamsoft Capture Vision.

static getVersion(): Promise<string>;

Return Value

The Version of DCVBarcodeReader.

getRuntimeSettings

Get the current runtime settings of DCVBarcodeReader.

getRuntimeSettings(): Promise<DBRRuntimeSettings>;

Return Value

An object of DBRRuntimeSettings that stores the runtime settings.

Code Snippet

let settings = await dbr.getRuntimeSettings();

updateRuntimeSettings

Update the barcode decoding settings with a DBRRuntimeSettings struct, a preset template (from the EnumDBRPresetTemplate items) or a JSON String.

updateRuntimeSettings(settings: String | DBRRuntimeSettings | EnumDBRPresetTemplate): Promise<void>;

Parameters

Settings: The parameter should be one of the following types:

settings (DBRRuntimeSettings): An object that stores DBRRuntimeSettings.
settings (EnumDBRPresetTemplate): One of the EnumDBRPresetTemplate member that indicates a preset template.
settings (String): A stringified JSON data that contains barcode decoding settings. The available settings include but not limited in DBRRuntimeSettings. You can access full feature of DBR when upload the settings from a JSON data.

Code Snippet

// Update runtime settings from a DBRRuntimeSettings object.
let settings = await dbr.getRuntimeSettings()
settings.expectedBarcodesCount = 5;
settings.timeout = 1000;
dbr.updateRuntimeSettings(settings)
// Update runtime settings from a preset template
dbr.updateRuntimeSettings(Dynamsoft.EnumDBRPresetTemplate.VIDEO_SPEED_FIRST)
// Update runtime settings from a JSON template.
dbr.updateRuntimeSettings("{\"ImageParameter\":{\"BarcodeFormatIds\":[\"BF_ALL\"],\"BarcodeFormatIds_2\":null,\"DeblurLevel\":0,\"ExpectedBarcodesCount\":0,\"LocalizationModes\":[{\"Mode\":\"LM_SCAN_DIRECTLY\",\"ScanDirection\":1},{\"Mode\":\"LM_CONNECTED_BLOCKS\"}],\"Name\":\"video-speed-first\",\"ScaleDownThreshold\":2300,\"Timeout\":500},\"Version\":\"3.0\"}")

resetRuntimeSettings

Reset the barcode decoding settings to default value.

resetRuntimeSettings(): void;

outputRuntimeSettingsToString

Output the barcode decoding settings to string.

outputRuntimeSettingsToString(): Promise<string>;

Return Value

A string that stores the barcode decoding settings. The barcode settings string can be applied to debug barcode decoding settings.

startScanning

Start the barcode decoding thread.

startScanning(): void;

stopScanning

Stop the barcode decoding thread.

stopScanning(): void;

addResultListener

Specifies an event handler that fires after the library finishes scanning a frame.

addResultListener(listener: (results: BarcodeResult[]) => void): void;

Code Snippet

The following code snippet shows how to use barcode reader module to decode from video stream.

dbr.addResultListener((results) => {
    const resultElement = document.getElementById('show_result');
    var resultStr = ""
    if (results && results.length > 0) {
        for (i = 0; i < results.length; i++) {
            resultStr=resultStr + results[i].barcodeFormatString+":"+results[i].barcodeText+'\n'
        }
        resultElement.innerHTML = (resultStr)
    } else {
        resultElement.innerHTML = "No barcode detected in this frame."
    }
    document.querySelector('#camera_view').appendChild(resultElement)
})

setMinImageReadingInterval

Set the minimum image reading interval.

setMinImageReadingInterval(interval: number): void;

getMinImageReadingInterval

Get the minimum image reading interval.

getMinImageReadingInterval(): Promise<number>;