Why am I unable to scan an Aztec code in the helloworld sample?

For version 10 and above

let settings = await router.getSimplifiedSettings("ReadSingleBarcode");
settings.barcodeSettings.barcodeFormatIds =
  Dynamsoft.DBR.EnumBarcodeFormat.BF_AZTEC;
await router.updateSettings("ReadSingleBarcode", settings);
await router.startCapturing("ReadSingleBarcode");

For version 8 and version 9

The reason for this is that the JavaScript edition defaults to the compact engine, rather than the full engine. The compact engine currently only supports 1D, QR, PDF417, and DataMatrix codes.

To switch to the full engine, please call the following before creating the BarcodeReader/BarcodeScanner instance:

Dynamsoft.DBR.BarcodeScanner._bUseFullFeature = true;