BarcodeReader

class BarcodeReader

The BarcodeReader class is used for decoding barcodes from images.

let reader = await Dynamsoft.DBR.BarcodeReader.createInstance();
let results = await reader.decode(imageSource);
for(let result of results){
  console.log(result.barcodeText);
}

Index

Initialize the Engine

Static Property	Description
engineResourcePath	Specifies the WASM engine URL.
_bUseFullFeature	If set to `true`, uses the full WASM engine.

Static Method	Description
isLoaded	Checks if the decoding module is loaded.
loadWasm	Manually loads and compiles the decoding WASM module.

Create and Destroy Instance

Property	Description
bDestroyed	Indicates whether the instance has been destroyed.

Static Method	Description
createInstance	Creates a `BarcodeReader` instance.

Method	Description
destroy	Destroies the `BarcodeReader` instance.

Decode Barcodes

Method	Description
decode	Decodes barcodes from images, binary data, URLs, and more.
decodeBase64String	Decodes barcodes from a base64 encoded string.
decodeUrl	Decodes barcodes from a URL.
decodeBuffer	Decodes barcodes from raw image data.

Decoding Settings

Method	Description
getRuntimeSettings	Gets current runtime settings.
updateRuntimeSettings	Modifies and updates the current runtime settings.
resetRuntimeSettings	Resets runtime settings to default.
getModeArgument	Gets argument value for the specified mode parameter.
setModeArgument	Sets argument value for the specified mode parameter.

License

Property	Description
productKeys	Gets or sets the Dynamsoft Barcode Reader SDK product keys.
licenseServer	Specifies the license server URL.
handshakeCode	Uses Handshake Code to get authentication.
organizationID	Uses Organization ID to get authentication.
sessionPassword	Specifies a password to protect the Handshake Code from abuse.

Others

Static Property	Description
version	Gets the current product version.

Property	Description
bSaveOriCanvas	If set to `true`, saves the original image in `oriCanvas` .
oriCanvas	An canvas object that holds the original image.

Static Method	Description
detectEnvironment	Detects environments and gets a report.

Initialize the Engine

engineResourcePath

static engineResourcePath: string

Manually specifies the URL of Barcode Reader SDK engine (WASM) . The property needs to be set before loadWasm.

Dynamsoft.DBR.BarcodeReader.engineResourcePath = "https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@8.2.5/dist/";
await Dynamsoft.DBR.BarcodeReader.loadWasm();

_bUseFullFeature

static _bUseFullFeature: boolean = false

Whether to use full WASM engine. The property needs to be set before loadWasm. The default is ‘false’.
```
 DBR.BarcodeReader._bUseFullFeature = true;
 await DBR.BarcodeReader.loadWasm();
```
Learn more about differences between compact and full WASM engines.

isLoaded

static isLoaded(): boolean

Checks if the decoding module is loaded.

loadWasm

static loadWasm(): Promise<void>

Before most operations, loadWasm needs to be excuted firstly.

Most time, you do not need excute loadWasm manually. Because when you excute createInstance, loadWasm will be excuted implicitly.

Some properties can’t be changed after loadWasm.

Calling loadWasm in advance can avoid the long wait when createInstance.
```
window.addEventListener('DOMContentLoaded', (event) => {
   DBR.BarcodeReader.loadWasm();
 });
```

Create and Destroy Instance

bDestroyed

bDestroyed: boolean

Indicates whether the instance has been destroyed.

createInstance

static createInstance(): Promise<BarcodeReader>

Create a BarcodeReader instance.
```
 let reader = await Dynamsoft.DBR.BarcodeReader.createInstance();
```

destroy

destroy(): Promise<void>

Destroies the BarcodeReader instance. If your page needs to create new instances from time to time, don’t forget to destroy unused old instances to avoid possible memory leaks.

Decode Barcode

decode

decode (source: Blob | Buffer | ArrayBuffer | Uint8Array | Uint8ClampedArray

| HTMLImageElement | HTMLCanvasElement | HTMLVideoElement

| string): Promise<TextResult[]>

Decodes barcodes from an image.

The main decoding method can accept a variety of data types, including binary data, images, base64 (with MIME), URL, etc.

The image format can be png, jpeg, bmp, gif and a few others (some browsers support webp, tif).
```
let results = await reader.decode(blob);
for(let result of results){
    console.log(result.barcodeText);
}

let results2 = await reader.decode(htmlImageElement);
let results2 = await reader.decode(url);
 
// like `data:image/png;base64,iV************`
let results3 = await reader.decode(strBase64WithMime);
```
And you can get a frame from the HTMLVideoElement for barcode scanning.
```
// The frame currently played will be decoded.
let results;
try{
  results = await reader.decode(htmlVideoElement);
}catch(ex){
  // If no frame in the video, throws an exception.   
}
```
If you need to continuously decode a video, you can use BarcodeScanner instead.

@see decodeBase64String, decodeUrl

decodeBase64String

decodeBase64String(base64: string): Promise<TextResult[]>

The decoding method can accept base64 with or without MIME. e.g. data:image/jpg;base64,Xfjshekk.... or Xfjshekk....
```
let results = await reader.decodeBase64String(strBase64);
for(let result of results){
  console.log(result.barcodeText);
}
```

decodeUrl

decodeUrl(url: string): Promise<TextResult[]>

The decoding method can accept an URL. The URL source needs to be in the same domain or allowed Cross-Origin Resource Sharing (CORS).
```
let results = await reader.decodeUrl("./1.png");
for(let result of results){
    console.log(result.barcodeText);
}
```

decodeBuffer

decodeBuffer(
    buffer: Uint8Array | Uint8ClampedArray | ArrayBuffer | Blob | Buffer,
    width: number, height: number, stride: number,
    format: EnumImagePixelFormat
): Promise<TextResult[]>

Decodes barcodes from raw image data.

Decoding Settings

getRuntimeSettings

getRuntimeSettings(): Promise<RuntimeSettings>

Gets current runtime settings.

let settings = await reader.getRuntimeSettings();
settings.deblurLevel = 5;
await reader.updateRuntimeSettings(settings);

updateRuntimeSettings

updateRuntimeSettings(settings: RuntimeSettings | string): Promise<void>

Updates runtime settings with a given struct or a string of speed, balance or coverage to use preset settings for BarcodeReader.

The default runtime setting for BarcodeReader is coverage.
```
await reader.updateRuntimeSettings('balance');
let settings = await reader.getRuntimeSettings();
settings.barcodeFormatIds = Dynamsoft.DBR.EnumBarcodeFormat.BF_ONED;
await reader.updateRuntimeSettings(settings);
```

resetRuntimeSettings

resetRuntimeSettings(): Promise<void>

Resets all parameters to default values.
```
await reader.resetRuntimeSettings();
```

getModeArgument

getModeArgument(modeName: string, index: number, argumentName: string): Promise<string>

Gets argument value for the specified mode parameter.
```
let argumentValue = await reader.getModeArgument("BinarizationModes", 0, "EnableFillBinaryVacancy");
```
@see C++ getModeArgument

setModeArgument

setModeArgument(modeName: string, index: number, argumentName: string, argumentValue: string): Promise<string>

Sets argument value for the specified mode parameter.
```
await reader.setModeArgument("BinarizationModes", 0, "EnableFillBinaryVacancy", "1");
```
@see C++ setModeArgument

License

productKeys

static productKeys: string

Gets or sets the Dynamsoft Barcode Reader SDK product keys.

Dynamsoft.DBR.BarcodeReader.productKeys = "PRODUCT-KEYS";

For convenience, you can set productKeys in script tag instead.

<script src="https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@8.2.5/dist/dbr.js" data-productKeys="PRODUCT-KEYS"></script>

licenseServer

static licenseServer: string[] | string

Specifies the license server URL.

handshakeCode

static handshakeCode: string

Gets or sets the Dynamsoft Barcode Reader SDK handshake code. The handshakeCode is an alias of productKeys. Specifically refers to the key that requires network authentication.
```
Dynamsoft.DBR.BarcodeReader.handshakeCode = "123****-mytest";
```
For convenience, you can set handshakeCode in script tag instead.
```
<script src="https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@8.2.5/dist/dbr.js" data-handshakeCode="123****-mytest"></script>
```

organizationID

static organizationID: string

Use organization ID to get authentication from network. Keep handshakeCode empty if you want to use default handshake of the organization.
```
Dynamsoft.DBR.BarcodeReader.organizationID = "123****";
```
For convenience, you can set organizationID in script tag instead.
```
<script src="https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@8.2.5/dist/dbr.js" data-organizationID="123****"></script>
```

sessionPassword

static sessionPassword: string

Specifies a password to protect the Handshake Code.

Dynamsoft.DBR.BarcodeReader.handshakeCode = "123****-mytest";
Dynamsoft.DBR.BarcodeReader.sessionPassword = "@#$%****";

For convenience, you can set organizationID in script tag instead.

<script src="https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@8.2.5/dist/dbr.js" data-handshakeCode="123****-mytest" data-sessionPassword="@#$%****"></script>

Other

bSaveOriCanvas

bSaveOriCanvas: boolean = false;

Whether to save the original image into canvas.

reader.bSaveOriCanvas = true;
let results = await reader.decode(source);
document.body.append(reader.oriCanvas);

oriCanvas

readonly oriCanvas: HTMLCanvasElement | OffscreenCanvas

A canvas object that holds the original image.

reader.bSaveOriCanvas = true;
let results = await reader.decode(source);
document.body.append(reader.oriCanvas);

version

readonly static version: string

Gets the current product version. Needs to call after loadWasm.

console.log(Dynamsoft.DBR.BarcodeReader.version); // "loading...(JS 8.2.5.20210426)"
await Dynamsoft.DBR.BarcodeReader.loadWasm();
console.log(Dynamsoft.DBR.BarcodeReader.version); // "8.4.0.8960(JS 8.2.5.20210426)"

detectEnvironment

static detectEnvironment(): Promise<any>

Detects environments and gets a report.

console.log(Dynamsoft.DBR.BarcodeReader.detectEnvironment());
// {"wasm":true, "worker":true, "getUserMedia":true, "camera":true, "browser":"Chrome", "version":90, "OS":"Windows"}