Create
Destroy
StartScanner
StopScanner
DecodeImage
addEventListener
setScannerSettings
getScannerSettings
getVideoDevices
bin2String
IsScannerReady
getVersion
getLicenseInfo
getFrame



Creates and initializes barcode scanner object. This method creates a video element (and others) inside the HTML element with the ID "ScannerSettings.viewport.id", initializes all inside variables of the DSScanner object, initializes the WebAssembly library (datasymbol-sdk.wasm). After the scanner is created (onScannerReady event), you can start scanning (StartScanner).

Syntax

DSScanner.Create(scannerSettings);

Parameters

• scannerSettings - ScannerSettings object that defines all scanner properties

Return Value

No return value.

Example

var scannerSettings = {
	viewport: {
		id: 'datasymbol-barcode-viewport',
		width: 640,	//null means 100% width
	},
	camera: {
		resx: 640,
		resy: 480,
	},
	barcode: {
		barcodeTypes: ['Code128', 'DataMatrix'],
	},
};

DSScanner.addEventListener('onError', onError);
DSScanner.addEventListener('onBarcode', onBarcodeReady);

DSScanner.addEventListener('onScannerReady', function () {
	DSScanner.StartScanner();
});

DSScanner.Create(scannerSettings);

Note

Events:
onScannerReady
onError

Stops barcode decoding, turn off camera and free all resources. To start scanner working again need to call Create method.

Syntax

DSScanner.Destroy();

Return Value

No return value.

Note

Events:
onScannerDestroyed

Starts the scanning cycle of frames. To save energy (especially it is important for mobile devices), there is a pause between scanning frames that is specified by the parameter "ScannerSettings.scanner.FrameTimeout". By default the pause makes 100ms, you can change this value depending on your requirements.

Syntax

DSScanner.StartScanner();

Return Value

No return value.

Note

Events:
onScannerStarted

Stops the frame scanning cycle. The object of the scanner itself DSScanner is completely ready for use, and you can immediately restart scanning (StartScanner method).

Syntax

DSScanner.StopScanner([keepVideo[ = false ]]);

Parameters

• keepVideo - keep video preview (default - false)

Return Value

No return value.

Note

Events:
onScannerStopped

Decodes image file (png, jpg, bmp, etc.) with barcode. To work in this mode you should not pass the ScannerSettings.camera object. In this case the browser will not request the camera access. To avoid the image drawing you can omit the ScannerSettings.viewport object.

Syntax

DSScanner.DecodeImage(src [, listener]);

Parameters

• src - object that defines the File object or URL string.
• listener - the callback function that receives notification when image was decoded, the callback receives the same parameter as onBarcode event

Return Value

No return value.

Example

JavaScript

function onBarcodeReady (barcodeResult) {
    var barDataEl = document.getElementById('status');

	for (var i = 0; i < barcodeResult.length; ++i) {
	        var sBarcode = DSScanner.bin2String(barcodeResult[i]);
	        var sPoints = "";
	        for (var j = 0; j < 4; j++)
	            sPoints += "(" + barcodeResult[i].points[j].x + ", " + barcodeResult[i].points[j].y + "),";

	        barDataEl.innerHTML = barcodeResult[i].type + ": " + sBarcode + "|" + sPoints;
	        console.log(barDataEl.innerHTML);
    }
};

function onError(err) {
    var statusElement = document.getElementById('status');
    statusElement.innerHTML = 'Error: ' + err.message;
}

function CreateScanner(device){
    var scannerSettings = {
        scanner: {
            key: '',
        },
        viewport: {
            id: 'datasymbol-barcode-viewport',
        },
        barcode: {
            barcodeTypes: ['EAN13', 'UPCA', 'Code128', 'Code39', 'EAN8', 'DataMatrix', 'QRCode'],
			totalBarcodes: 7,
			uiLinearFindBarcodes: 7,
        },
    };

    DSScanner.addEventListener('onError', onError);
    DSScanner.addEventListener('onBarcode', onBarcodeReady);

    DSScanner.addEventListener('onScannerReady', function () {
        console.log('HTML onScannerReady');
        var statusElement = document.getElementById('status');
        statusElement.innerHTML = ' ';
    });

    DSScanner.Create(scannerSettings);
}

window.onload = function () {
	CreateScanner();
	document.getElementById('file-input').addEventListener('change', DecodeImage, false);	
}
    
function DecodeImage(e) {
	var file = e.target.files[0];
	if (!file)
		return;

	DSScanner.DecodeImage(file);
	//DSScanner.DecodeImage('/barcode.png');
}

HTML

<p id='status'>Downloading ...</p>
<div id="datasymbol-barcode-viewport" style="display:block;width:640px;height:480px;"></div>
Load File:<input type="file" id="file-input"'/>

Note

Events:
onBarcode
onImageDecoded
onError

Adds handlers for various events

Syntax

DSScanner.addEventListener(type, listener);

Parameters

• type - A case-sensitive string representing the event type to listen for. Find available events here
• listener - The function which receives a notification

Return Value

No return value.

Example

DSScanner.addEventListener('onScannerReady', function () {
	DSScanner.StartScanner();
});

Changes any scanner settings

Syntax

DSScanner.setScannerSettings(scannerSettings);

Parameters

• scannerSettings - ScannerSettings object that defines all scanner properties

Return Value

No return value.

Example

var scannerSettings = {
	camera: {
		resx: 800,
	},
};

DSScanner.setScannerSettings(scannerSettings);

Note

Events:
onScannerReady
onError

Returns the copy of ScannerSettings object contained inside DSScanner object.

Syntax

var scannerSettings = DSScanner.getScannerSettings();

Return Value

ScannerSettings object

Returns cameras that can be used on this device.

Syntax

DSScanner.getVideoDevices(listener[, requestLabel[ = false ]]);

Parameters

• listener - the function which receives the video devices
• requestLabel - request camera label. If "true" Firefox will ask for permision to access the camera twice

Return Value

No return value.

Example

DSScanner.getVideoDevices(function (devices) {
	devices.forEach(function (device) {
		console.log("device:" + device.label + '|' + device.id);
	});
});

Returns barcode string converted from binary data.

Syntax

var barcodeString = DSScanner.bin2String(barcodeResult [, dataEncoding]);

Parameters

• barcodeResult - object with barcode properties returned by onBarcode event
• dataEncoding - encoding type of binary data in barcodeResult, default - 'utf8', possible values:

  'utf-8', 'ibm866', 'iso-8859-2', 'iso-8859-3', 'iso-8859-4', 'iso-8859-5', 'iso-8859-6', 'iso-8859-7', 'iso-8859-8', 'iso-8859-8i', 'iso-8859-10', 'iso-8859-13', 'iso-8859-14', 'iso-8859-15', 'iso-8859-16', 'koi8-r', 'koi8-u', 'macintosh', 'windows-874', 'windows-1250', 'windows-1251', 'windows-1252', 'windows-1253', 'windows-1254', 'windows-1255', 'windows-1256', 'windows-1257', 'windows-1258', 'x-mac-cyrillic', 'gbk', 'gb18030', 'hz-gb-2312', 'big5', 'euc-jp', 'iso-2022-jp', 'shift-jis', 'euc-kr', 'iso-2022-kr', 'utf-16be', 'utf-16le', 'x-user-defined',

Return Value

String value

Example

function onBarcodeReady (barcodeResult) {
	for (var i = 0; i < barcodeResult.length; ++i) {
        var barcodeString = DSScanner.bin2String(barcodeResult[i], 'sjis');
		console.log(barcodeString);
	}
}

Returns value that determines scanner ready state.

Syntax

var bScannerIsReady = DSScanner.IsScannerReady();

Return Value

boolean value

Example

console.log(DSScanner.IsScannerReady());

Returns barcode Web SDK and barcode scanner core versions.

Syntax

var version = DSScanner.getVersion();

Return Value

Object
{ websdk:WEBSDK, coresdk:CORESDK }

Example

console.log(DSScanner.getVersion());

Returns license information. If Barcode Web SDK works in demo mode then all fields are empty.

Syntax

var li = DSScanner.getLicenseInfo();

Return Value

Object

{
    licenseInfo: 'MyCompanyName ...',
    edition: 'professional',	//or 'standard'
    decoders: 'linear,pdf417,datamatrix,qrcode,azteccode',	//or any other combination
    expDate: '2020-02-29'	//year-month-day, epiration date (or empty if for life time)
}

Example

DSScanner.addEventListener('onInitialized', function () {
	var li = DSScanner.getLicenseInfo();
	console.log("licenseInfo:\n" + li.licenseInfo);
	console.log("edition: " + li.edition);
	console.log("decoders: " + li.decoders);
	console.log("expDate: " + li.expDate);
});

Returns the current video frame.

Syntax

var imageData = DSScanner.getFrame();

Return Value

ImageData Object

Example

//myCanvas - CANVAS HTML element with 'myCanvas' id
//<canvas id='myCanvas' width='320' height='240'></canvas>
var canvas = document.getElementById('myCanvas');
var ctx = canvas.getContext('2d');

var imageData = DSScanner.getFrame();

canvas.width = imageData.width;
canvas.height = imageData.height;

ctx.putImageData(imageData, 0, 0);	//draw current frame in 'myCanvas'