---
title: Machine-readable object types
framework: avfoundation
role: collectionGroup
role_heading: API Collection
path: avfoundation/machine-readable-object-types
---

# Machine-readable object types

Constants used to specify the type of barcode to scan.

## Overview

Overview These constants are used in conjunction with the AVCaptureMetadataOutput class’s metadataObjectTypes property to specify the type (“symbology”) of barcode to scan. When a barcode is detected, the type property of AVMetadataMachineReadableCodeObject reflects the constant for the detected barcode’s symbology.

## Topics

### Constants

- [upce](avfoundation/avmetadataobject/objecttype/upce.md)
- [code39](avfoundation/avmetadataobject/objecttype/code39.md)
- [code39Mod43](avfoundation/avmetadataobject/objecttype/code39mod43.md)
- [ean13](avfoundation/avmetadataobject/objecttype/ean13.md)
- [ean8](avfoundation/avmetadataobject/objecttype/ean8.md)
- [code93](avfoundation/avmetadataobject/objecttype/code93.md)
- [code128](avfoundation/avmetadataobject/objecttype/code128.md)
- [pdf417](avfoundation/avmetadataobject/objecttype/pdf417.md)
- [qr](avfoundation/avmetadataobject/objecttype/qr.md)
- [aztec](avfoundation/avmetadataobject/objecttype/aztec.md)
- [interleaved2of5](avfoundation/avmetadataobject/objecttype/interleaved2of5.md)
- [itf14](avfoundation/avmetadataobject/objecttype/itf14.md)
- [dataMatrix](avfoundation/avmetadataobject/objecttype/datamatrix.md)