---
title: symbologies
framework: vision
role: symbol
role_heading: Instance Property
path: vision/vndetectbarcodesrequest/symbologies
---

# symbologies

The barcode symbologies that the request detects in an image.

## Declaration

```swift
var symbologies: [VNBarcodeSymbology] { get set }
```

## Discussion

Discussion By default, a request scans for all symbologies. Specify a subset of symbologies to limit the request’s detection range. note: Setting a revision on the request resets the symbologies to all symbologies for the specified revision.

## See Also

### Specifying Symbologies

- [supportedSymbologies()](vision/vndetectbarcodesrequest/supportedsymbologies().md)
- [coalesceCompositeSymbologies](vision/vndetectbarcodesrequest/coalescecompositesymbologies.md)
- [VNBarcodeSymbology](vision/vnbarcodesymbology.md)
- [supportedSymbologies](vision/vndetectbarcodesrequest/supportedsymbologies.md)