---
title: VNHomographicImageRegistrationRequest
framework: vision
role: symbol
role_heading: Class
path: vision/vnhomographicimageregistrationrequest
---

# VNHomographicImageRegistrationRequest

An image-analysis request that determines the perspective warp matrix necessary to align the content of two images.

## Declaration

```swift
class VNHomographicImageRegistrationRequest
```

## Overview

Overview Create and perform a homographic image registration request to align content in two images through a homography. A homography is an isomorphism of projected spaces, a bijection that maps lines to lines.

## Topics

### Accessing the Results

- [results](vision/vnhomographicimageregistrationrequest/results.md)

### Identifying Request Revisions

- [VNHomographicImageRegistrationRequestRevision1](vision/vnhomographicimageregistrationrequestrevision1.md)

## Relationships

### Inherits From

- [VNImageRegistrationRequest](vision/vnimageregistrationrequest.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSCopying](foundation/nscopying.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)

## See Also

### Image alignment

- [Aligning Similar Images](vision/aligning-similar-images.md)
- [VNTargetedImageRequest](vision/vntargetedimagerequest.md)
- [VNImageRegistrationRequest](vision/vnimageregistrationrequest.md)
- [VNTranslationalImageRegistrationRequest](vision/vntranslationalimageregistrationrequest.md)
- [VNTrackTranslationalImageRegistrationRequest](vision/vntracktranslationalimageregistrationrequest.md)
- [VNTrackHomographicImageRegistrationRequest](vision/vntrackhomographicimageregistrationrequest.md)
- [VNImageAlignmentObservation](vision/vnimagealignmentobservation.md)
- [VNImageTranslationAlignmentObservation](vision/vnimagetranslationalignmentobservation.md)
- [VNImageHomographicAlignmentObservation](vision/vnimagehomographicalignmentobservation.md)