---
title: "disparity(in:sourceDisparity:detectionType:priorDisparity:)"
framework: cinematic
role: symbol
role_heading: Type Method
path: "cinematic/cndetection-swift.struct/disparity(in:sourcedisparity:detectiontype:priordisparity:)"
---

# disparity(in:sourceDisparity:detectionType:priorDisparity:)

Determines the disparity to use to focus on the object in the rectangle.

## Declaration

```swift
static func disparity(in normalizedRect: CGRect, sourceDisparity: CVPixelBuffer, detectionType: CNDetectionType, priorDisparity: Float? = nil) -> Float
```

## Parameters

- `normalizedRect`: The rectangle within the image where the object occurs, normalized such that (0.0, 0.0) is the top-left and (1.0, 1.0) is the bottom-right.
- `sourceDisparity`: The disparity buffer containing depth information
- `detectionType`: The type of object expected within the rectangle. Pass `CNDetectionTypeUnknown` if unknown.
- `priorDisparity`: The disparity of the object in the prior frame. This helps ensure the object isn’t mistaken for another that enters the same rectangle. Pass `NAN` if there’s no known prior, such as in the first frame in which the tracked object.

## Return Value

Return Value A float representing the disparity to use to focus on the object in the rectangle.