Dynamsoft JavaScript Barcode SDK for Node and Web
Version: 7.1.2
Dynamsoft BarcodeReader SDK for Javascript is a JavaScript API for barcode scanning based on the WebAssembly technology. It supports real-time localization and decoding of various barcode types. The library is capable of scanning barcodes from static images as well as directly from live video streams. It also supports reading multiple barcodes at once.
Features
-
Supported Symbologies:
1D barcode: Code 39
, Code 93
, Code 128
, Codabar
, EAN-8
, EAN-13
, UPC-A
, UPC-E
, Interleaved 2 of 5
(ITF), Industrial 2 of 5
(Code 2 of 5 Industry, Standard 2 of 5, Code 2 of 5), ITF-14
.
2D barcode: PDF417
, QR
, DataMatrix
, and Aztec
.
-
Supported Data Sources: Blob
, HTMLImageElement
, HTMLVideoElement
, and URL
, etc.
-
Browser Compatibility:
Browser Name | Version |
---|
Chrome | v57+ (v59+ on Android/iOS1) |
Firefox | v52+ (v55+ on Android/iOS1) |
Edge | v16+ |
Safari2 | v11+ |
1 On iOS, camera video streaming only works in Safari.
2 Safari 11.2.2 ~ 11.2.6 are not supported.
Node.js v8+ is also supported. However, it can only use BarcodeReader
to read barcode from still-images. The video stream reader object BarcodeScanner
is not supported.
Quick Usage
Node
var dbr = require('dynamsoft-javascript-barcode');
dbr.BarcodeReader.productKeys = 'LICENSE-KEY';
dbr.BarcodeReader.createInstance().then(reader => {
reader.decode('sample.png').then(results => {
for(var i = 0; i < results.length; ++i){
console.log(results[i].BarcodeText);
}
reader.destroy();
});
});
Web
<!DOCTYPE html>
<html>
<body>
<script src="node_modules/dynamsoft-javascript-barcode/dist/dbr.min.js" data-productKeys="LICENSE-KEY"></script>
<script>
let barcodeScanner = null;
Dynamsoft.BarcodeScanner.createInstance({
onFrameRead: results => {console.log(results);},
onUnduplicatedRead: (txt, result) => {alert(txt);}
}).then(scanner => {
barcodeScanner = scanner;
barcodeScanner.show();
});
</script>
</body>
</html>
Table of Contents
Live Demo
The following is a screenshot of the live demo. Try it here.
Getting Started: HelloWorld
This section will help you use the library to build a simple web application to decode barcodes from a video stream.
Basic Requirements:
-
Internet connection
-
Camera Access
Step One: Write the code in minutes!
Create an HTML file with the following content. Deploy it to your web server if you have it already.
- The sample is missing one piece of information to actually work which is the field
LICENSE-KEY
, you can acquire a trial key here and replace the field with your key. - If you don't have a ready-to-use web server and you happen to have a package manager like
npm
or yarn
, you can set up a simple http server in minutes. Check out http-server on npm or yarn.
<!DOCTYPE html>
<html>
<body>
<script src="https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@7/dist/dbr.min.js" data-productKeys="LICENSE-KEY"></script>
<script>
let barcodeScanner = null;
Dynamsoft.BarcodeScanner.createInstance({
onFrameRead: results => {console.log(results);},
onUnduplicatedRead: (txt, result) => {alert(txt);}
}).then(scanner => {
barcodeScanner = scanner;
barcodeScanner.show();
});
</script>
</body>
</html>
Try in JSFiddle
Step Two: Tackle a few issues
Open the file in your browser (must be one that is supported) and there will be a pop-up asking for permission to access the camera. Once the access is granted, you will see the video stream in the default UI of the BarcodeScanner.
General Issue one
If you open the HTML file as file:///
or http://
, the following error may appear in the browser console
[Deprecation] getUserMedia() no longer works on insecure origins. To use this feature, you should consider switching your application to a secure origin, such as HTTPS. See https://goo.gl/rStTGz for more details.
In Safari 12 the error is
Trying to call getUserMedia from an insecure document.
As the error states, to access the camera with the API getUserMedia, a secure channel (https://
) is required.
If you use Chrome or Firefox, you might not get the error because these two browsers allow camera access via file:///
and http://localhost
.
To make sure your web application can access the camera, try to configure your web server to support HTTPS. The following links may help.
General Issue Two
For testing purposes, a self-signed certificate can be used when configuring HTTPS. When accessing the site, the browser might say "the site is not secure
". In this case, go to the certificate settings and trust this certificate.
In a production environment, you will need a valid HTTPS certificate that does not have this issue. If you don't have one yet, you can get a free one from Let’s Encrypt. Of course, you are advised to apply for a paid certificate from companies such as Verisign, GeoTrust, etc.
Step Three: Time to scan!
Put something with a barcode in front of the camera and you'll see it located and decoded right in the UI.
Step Four: Dive into the code
Now, take a look at the sample code. You can find that there is nothing but two scripts inside the <body>
-
The following script includes the core library in the application via a jsDelivr CDN
<script src="https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@7/dist/dbr.min.js" data-productKeys="LICENSE-KEY"></script>
The same can be done with other CDNs like unpkg as well
<script src="https://unpkg.com/dynamsoft-javascript-barcode@7/dist/dbr.min.js" data-productKeys="LICENSE-KEY"></script>
-
The following script initializes and uses the library:
<script>
let barcodeScanner = null;
Dynamsoft.BarcodeScanner.createInstance({
onFrameRead: results => {console.log(results);},
onUnduplicatedRead: (txt, result) => {alert(txt);}
}).then(scanner => {
barcodeScanner = scanner;
barcodeScanner.show();
});
</script>
For now, pay attention to the following two events.
onFrameRead
This event is triggered after a single frame is scanned. The results
object contains all the barcode results that the library found on this frame.onUnduplicatedRead
This event is triggered when a new barcode (not a duplicate) is found. txt
holds the barcode text value while result
is an object that holds details of the found barcode.
In the following sections, you'll find more detailed information on how the library works and how you can customize it to your needs.
Getting Started: Take a closer look
Initializing
The library is based on the WebAssembly standard, therefore, on first use, it needs some time to download and compile the WebAssembly files. After the first use, the program will cache the wasm file in the IndexedDB
so that the next time you can just open and play.
Dynamsoft.BarcodeReader.loadWasm
is the API used to start the initialization. However, other APIs like Dynamsoft.BarcodeReader.createInstance
, Dynamsoft.BarcodeScanner.createInstance
will call loadWasm
internally so it is not necessary to explicitly call loadWasm
when using these APIs.
Including the library with a script tag doesn't automatically initializes the library.
The initialization includes the following steps:
- Download
Dynamsoft.BarcodeReader._onWasmDownloaded
is a built-in callback that gets triggered when the WebAssembly files are downloaded. As the downloading only happens on the first use, this callback will only be triggered once as well (assume that the user doesn't clear the old cached files).
- Compile
The WebAssembly files are automatically compiled once downloaded. The compilation time varies among different devices & browsers. While it takes less than tenth of a seconds on latest phones or PCs, it may take seconds on some older devices.
- Initialize
The library needs to initialize every time the page loads. Use the following code to listen to the initialization process:
Dynamsoft.BarcodeReader.loadWasm()
.then(()=>{ }, ex=>{console.error(ex.message||ex);})
You can use Dynamsoft.BarcodeReader.createInstance
or Dynamsoft.BarcodeScanner.createInstance
as well, to listen to the initialization process during createInstance
.
Configuring Scanner Settings
When creating an instance of the BarcodeScanner
object, there are a number of configuration options. The following code shows some of the most useful ones:
let barcodeScanner = null;
Dynamsoft.BarcodeScanner.createInstance({
onFrameRead: results => {console.log(results);},
onUnduplicatedRead: (txt, result) => {alert(txt);}
}).then(scanner => {
barcodeScanner = scanner;
barcodeScanner.updateVideoSettings({ video: { width: 1280, height: 720, facingMode: "environment" } });
let runtimeSettings = barcodeScanner.getRuntimeSettings();
runtimeSettings.BarcodeFormatIds = Dynamsoft.EnumBarcodeFormat.OneD | Dynamsoft.EnumBarcodeFormat.QR_CODE;
runtimeSettings.localizationModes = [2,16,4,8,0,0,0,0];
runtimeSettings.minResultConfidence = 30;
barcodeScanner.updateRuntimeSettings(runtimeSettings);
let scanSettings = barcodeScanner.getScanSettings();
scanSettings.duplicateForgetTime = 20000;
scanSettings.intervalTime = 300;
barcodeScanner.updateScanSettings(scanSettings);
barcodeScanner.show();
})
Try in JSFiddle
As you can see in the code, there are basically three categories of configurations.
-
get/updateVideoSettings
: Configures the data source, I.E., the video stream. These settings include which camera to use , the resolution, etc.. Check out more information here.
-
get/updateRuntimeSettings
: Configures the decode engine. Find a full list of these settings and their corresponding descriptions here. Below lists the recommended settings for specific usage.
Try in JSFiddle
fast
let settings = barcodeScanner.getRuntimeSettings();
settings.localizationModes = [2, 0, 0, 0, 0, 0, 0, 0];
settings.deblurLevel = 0;
barcodeScanner.updateRuntimeSettings(settings);
1D
let settings = barcodeScanner.getRuntimeSettings();
settings.localizationModes = [2, 4, 8, 0, 0, 0, 0, 0];
settings.deblurLevel = 0;
barcodeScanner.updateRuntimeSettings(settings);
2D
let settings = barcodeScanner.getRuntimeSettings();
settings.localizationModes = [2, 4, 8, 0, 0, 0, 0, 0];
settings.deblurLevel = 2;
barcodeScanner.updateRuntimeSettings(settings);
-
get/updateScanSettings
: Configures the scanner. For v7.0, the configurations for the scanner are limited to duplicateForgetTime
and intervalTime
.
Customizing the UI
While the library provides a built-in BarcodeScanner
which has its own UI, you are free to use your own UI. Check out the following code on how it's done.
<!DOCTYPE html>
<html>
<body>
<div id="div-video-container">
<video class="dbrScanner-video" playsinline="true"></video>
</div>
<script src="https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@7/dist/dbr.min.js" data-productKeys="LICENSE-KEY"></script>
<script>
let barcodeScanner = null;
Dynamsoft.BarcodeScanner.createInstance({
UIElement: document.getElementById('div-video-container'),
onFrameRead: results => {console.log(results);},
onUnduplicatedRead: (txt, result) => {alert(txt);}
}).then(scanner => {
barcodeScanner = scanner;
barcodeScanner.show();
});
</script>
</body>
</html>
Try in JSFiddle
The code has specified the UIElement
with the ID div-video-container
as the data source element and has put a video element inside to show the camera video stream.
Important: The class name of the video element must be dbrScanner-video
.
<video class="dbrScanner-video" playsinline="true"></video>
Next, you can add the camera list and resolution list.
If the class names match the default ones which are dbrScanner-sel-camera
and dbrScanner-sel-resolution
, the library will automatically populate the lists and handle the camera/resolution switching automatically.
<select class="dbrScanner-sel-camera"></select>
Try in JSFiddle
<select class="dbrScanner-sel-resolution"></select>
8 default resolutions will automatically show up.
Try in JSFiddle
Too many resolutions may be overwhelming for end users. Check out the following code on how to offer your own resolution options.
<select class="dbrScanner-sel-resolution">
<option class="dbrScanner-opt-gotResolution" value="got"></option>
<option data-width="1920" data-height="1080">1920 x 1080</option>
<option data-width="1280" data-height="720">1280 x 720</option>
<option data-width="640" data-height="480">640 x 480</option>
</select>
Possible Issue: Generally you need to provide a resolution that the camera supports. However, in case a camera does not support a specified resolution, it usually will just use the nearest supported resolution. As a result, the selected resolution may not be the actual resolution.
Resolution: To take care of this issue, you can add a option with the class name dbrScanner-opt-gotResolution
(as shown above) which the library will then use to show the actual resolution being used.
Try in JSFiddle
Customizing Further
You may not want to use elements with the default class names to show the camera list or resolution list. In this case, you need to populate the two lists yourself.
For camera list, you can use the API getAllCameras()
to get all available cameras and then populate them on the page.
<select id="custom-camera-list"></select>
let currentCamera = "";
let cameraList = document.getElementById("custom-camera-list");
barcodeScanner.show()
.then(() => barcodeScanner.getCurrentCamera())
.then(camera => {
currentCamera = camera;
})
.then(() => barcodeScanner.getAllCameras())
.then(allCameras => {
cameraList.options.length = 0;
for (let i = 0; i < allCameras.length; i++) {
let camera = allCameras[i];
cameraList.options.add(new Option(camera.label, camera.deviceId));
if (camera.deviceId == currentCamera.deviceId)
cameraList.selectedIndex = i;
}
});
Switch to the selected camera.
cameraList.onchange = () => {
barcodeScanner.setCurrentCamera(cameraList.options[cameraList.selectedIndex].value);
};
Try in JSFiddle
If you have more than one camera and would like to use a certain one of them. Try out the code below.
barcodeScanner.show()
.then(() => barcodeScanner.getAllCameras())
.then(allCameras => {
for (let camera of allCameras) {
if (camera.label == 'Your-Camera-Name') {
barcodeScanner.setCurrentCamera(camera.deviceId);
break;
}
}
});
Try in JSFiddle
For resolution list, you can show your preferred resolutions and use the API setResolution
to set the selected option.
<select id="custom-camera-resolution">
<option data-width="1920" data-height="1080">1920 x 1080</option>
<option data-width="1280" data-height="720">1280 x 720</option>
<option data-width="640" data-height="480">640 x 480</option>
</select>
let resolutionList = document.getElementById("custom-camera-resolution");
resolutionList.onchange = () => {
barcodeScanner.setResolution(
resolutionList.options[resolutionList.selectedIndex].getAttribute("data-width"),
resolutionList.options[resolutionList.selectedIndex].getAttribute("data-height")
);
};
Try in JSFiddle
Advanced Usage
Print out log for better debugging
Include the following in your code to print internal logs in the console.
Dynamsoft.BarcodeReader._onLog = console.log;
Show found barcodes
Try the following code to show found barcodes in input
elements on the page
<input id="ipt-0">
<input id="ipt-1">
<input id="ipt-2">
let iptIndex = 0;
let barcodeScanner = null;
Dynamsoft.BarcodeScanner.createInstance({
UIElement: document.getElementById('div-video-container'),
onFrameRead: results => {console.log(results);},
onUnduplicatedRead: (txt)=>{
document.getElementById('ipt-' + iptIndex).value = txt;
if(3 == ++iptIndex){
barcodeScanner.onUnduplicatedRead = undefined;
barcodeScanner.stop();
barcodeScanner.hide();
}
}
}).then(scanner => {
barcodeScanner = scanner;
barcodeScanner.show();
});
Try in JSFiddle
Read a specific area/region
To speed up the scanning process, you can choose to scan only a specific area/region.
let settings = barcodeScanner.getRuntimeSettings();
settings.region.measuredByPercentage = 1;
settings.region.left = 25;
settings.region.top = 25;
settings.region.right = 75;
settings.region.bottom = 75;
barcodeScanner.updateRuntimeSettings(settings);
Try in JSFiddle
Custom Deployment
The library consists of several files. In the sample code above, we used it via a CDN which hosts all the necessary files. Most of the time using the CDN is enough. However, you may prefer to deploy the library on your own server in some cases. For example, in an environment without internet access. The following shows how it's done.
- Step one: Place the files
Create a directory called dist
on your server and put the following files in there.
Download zip to get these files.
dbr-<version>.min.js
dbr-<version>.wasm.min.js
dbr-<version>.wasm
dbr-<version>.wasm.withio.min.js
dbr-<version>.withio.wasm
dbr-<version>.esm.min.js
It's recommended to place all the files. If you want to place only the necessary ones, check out the following instructions.
dbr-<version>.min.js
dbr-<version>.wasm.min.js
dbr-<version>.wasm
dbr-<version>.min.js
dbr-<version>.wasm.withio.min.js
dbr-<version>.withio.wasm
- web + document + es6 module:
dbr-<version>.min.esm.js
dbr-<version>.wasm.min.js
dbr-<version>.wasm
- web + worker + es6 module:
dbr-<version>.min.esm.js
dbr-<version>.wasm.withio.min.js
dbr-<version>.withio.wasm
dbr-<version>.min.js
dbr-<version>.wasm.withio.min.js
dbr-<version>.withio.wasm
-
Step two: Configure the server
Make sure that your webserver serves the *.wasm
file with Content-Type: application/wasm
. Otherwise the browser won't be able to recognize it.
Basically, all you need to do is set the MIME type for .wasm
to application/wasm
.
Different servers are configured differently, below lists a few popular ones
Changelog
7.1.2
Add a more advanced react example.
7.1.1
Fix bug about torch. Torch (flashlight) is supported in chrome with the supported cameras.
7.1.0
Updated algorithm to 7.1.
Improved the speed to download, build and initialize the library.
Improved the readability of barcode result text by using UTF-8 encoding.
Improved developer’s guide to be clearer and more precise.
Renamed setScanSettings for updateScanSettings for naming consistence.
7.0.0
Built Dynamsoft Barcode Reader 7.0 to JS(WebAssembly) version.
Added the capability to enable/disable the torch/flashlight of a mobile device (when available, only Chrome on Android).
Added APIs for finer video control. These APIs are getAllCameras, getCurrentCamera, setCurrentCamera, getResolution, setResolution.
6.5.2.1
Improve video decoding capabilities.
6.5.2
Built Dynamsoft Barcode Reader 6.5.2 to JS(WebAssembly) version.
Walkaround for certain scenarios of Content Security Policy (CSP).
Add a setting can turn off the feature of using IndexedDB.
6.5.1
Added video view for barcode scan. Compatible with Node.js.
6.4.1.3
The dbr-6.4.1.3.wasm
size is now reduced to 3.41M.
6.4.1.1
Fixed a memory leak related to mTimeout
in RuntimeSettings
.
6.4.1.0
Built Dynamsoft Barcode Reader 6.4.1 to JS(WebAssembly) version.
Combined the normal and the mobile version into one.
6.3.0.2
Added built-in Worker support.
6.3.0.1
Set dbr-<version>.js
(stable) as the main branch.
Added dbr-<version>.mobile.js
(smaller, compiles quicker, requires less memory, but not as stable) for mobile Safari.
6.3.0
Dynamsoft Barcode Reader JS/WebAssembly version released.
API Documentation
Decoding Images:
BarcodeReader
Decoding Video Stream:
BarcodeScanner
License Activation
It takes several steps to activate a purchased license, the following steps assume you have already acquired a commercial license from Dynamsoft. If you haven't done so, you can purchase here.
-
Step One : Create a Dynamsoft Account
If you don't have a Dynamsoft Account yet, sign up here.
-
Step Two : Log into Dynamsoft Customer Portal
Once logged in, click Barcode Reader SDK on the menu bar on the left under License Center and you should be able to see your purchased key on the right pane.
-
Step Three : Activate the License
Under Status, click the link Activate Now where you will be asked to input a domain which your license key will be bound to. The domain binding is a security feature to protect your license, although it's optional, it's highly recommended.
A few examples of the domain
www.dynamsoft.com
demo.dynamsoft.com
*.dynamsoft.com
*.dynamsoft.com;*.yoursite.com
-
Step Four : Use the License
You may have noticed that in all the samples above, we have the following line of code
<script src="https://cdn.jsdelivr.net/npm/dynamsoft-javascript-barcode@7/dist/dbr.min.js" data-productKeys="LICENSE-KEY"></script>
To use your license, you simply need to replace LICENSE-KEY
with it.
License Agreement
https://www.dynamsoft.com/Products/barcode-reader-license-agreement.aspx#javascript
Contact Us
If there are any questions, please feel free to contact support@dynamsoft.com.