experimental.md

Experimental features

Some of the features that are supported by the library but not officially recommended to be used across devices. If you find any of the features useful, please feel free to use them at your own risk, they are configurable in the library. In future, based on the support level and compatibility, some of these features will get upgraded to general feature list.

Using experimental native BarcodeDetector API

Turning on this flag allows using native BarcodeDetector api now being introduced in web browsers for code scanning instead of ZXing library we use officially.

How to turn this on

It can be turned on using new config called useBarCodeDetectorIfSupported added to experimentalFeatures config group. It's off (value = false) by default. If set to on (value = true) and the BarcodeDetector is supported by the browser, it'll be used for scanning all the kind of 1d and 2d codes.

Html5Qrcode class

function onScanSuccess(decodedText, decodedResult) {
    /** Handle success condition. */
}

let html5qrcode = new Html5Qrcode("reader", {
    // Use this flag to turn on the feature.
    experimentalFeatures: {
        useBarCodeDetectorIfSupported: false
    }
});

const scanConfig = { fps: 10, qrbox: 250 };
// If you want to prefer front camera
html5qrcode.start({ facingMode: "user" }, scanConfig, onScanSuccess);

Html5QrcodeScanner class

function onScanSuccess(decodedText, decodedResult) {
    /** Handle success condition. */
}

let html5QrcodeScanner = new Html5QrcodeScanner(
    "reader", 
    { 
        fps: 10,
        qrbox: 250,
        // Use this flag to turn on the feature.
        experimentalFeatures: {
            useBarCodeDetectorIfSupported: false
        }
    });
html5QrcodeScanner.render(onScanSuccess);

performance

Native scanning library seems to be giving better performance for scanning QR codes than with Zxing library.

Device	With ZXing	With BarcodeDecoder
Macbook Pro 16, Google Chrome	21 ms	10 ms
Pixel 4 Google Chrome	56 ms	23 ms
Pixel 4a Google Chrome	92 ms	47.3 ms
(low end) Android Device Google Chrome	373 ms	77.5 ms

Not supported on:

• Macbook Pro 16, Safari (macOS Big Sur)

More references

• https://web.dev/shape-detection/#barcodedetector