---
title: VNDetectContourRequestRevision1
framework: vision
role: symbol
role_heading: Global Variable
path: vision/vndetectcontourrequestrevision1
---

# VNDetectContourRequestRevision1

A constant for specifying revision 1 of the contours detection request.

## Declaration

```swift
var VNDetectContourRequestRevision1: Int { get }
```