How to improve scanning qr codes?

Question

I am creating some kind of streaming app. I have open camera and I implemented scanning qr codes in background using https://pub.dev/packages/google_ml_kit

Here is my code for that:

var stream = await navigator.mediaDevices
        .getUserMedia({'video': true, 'audio': true});
    setState(() {
      _localRenderer.srcObject = stream;
    });
    streamTrack = stream.getVideoTracks().first;
    await Future.delayed(Duration(seconds: 2));
    _getSnapshotTimer = Timer.periodic(Duration(seconds: 1), (timer) async {     // skanowanie kodów QR
      final frame = await streamTrack.captureFrame();
      File file = await File('${_tempDir.path}/image.png').create();
      file.writeAsBytesSync(frame.asUint8List());
      final _qrCodes =
          await _qrCodeScanner.processImage(InputImage.fromFile(file));

My problem is because of that video from camera is lagging every second. There is like a little freeze. There is some option to improve this? To make video from camera smooth all time?