# Improve the Performance of BarcodeScanner

Using a template file is the quickest way to improve the performance of BarcodeScanner. A template file is a JSON file (or JSON string) that includes a series of algorithm parameter settings. [Contact us](https://www.dynamsoft.com/company/customer-service/#contact) to get a customized template for your scanner.

1. Add a **Templates** folder to the assets folder of your project at **src\main\assets\Templates**. Put your JSON file in the **Templates** folder. Here we use a **ReadQRCode.json** file as an example.

    <div align="left">
    <p><img src="../../assets/init-settings-from-file-ios.png" alt="initSettings" width="50%" /></p>
    </div>

2. Specify the template file via property `templateFile`

   <div class="sample-code-prefix"></div>
   >- Objective-C
   >- Swift
   >
   >1. 
   ```objc
   DSBarcodeScannerConfig *config = [[DSBarcodeScannerConfig alloc] init];
   config.templateFile = @"ReadQRCodes.json";
   ```
   2. 
   ```swift
   let config = BarcodeScannerConfig()
   config.templateFile = "ReadQRCodes.json"
   ```

**Related APIs**

- [`templateFile`](/barcode-reader/docs/mobile/programming/objectivec-swift/api-reference/barcode-scanner/barcode-scanner-config.html#templatefile)