---
title: CVImageLogTransferFunction
framework: corevideo
role: symbol
role_heading: Enumeration
path: corevideo/cvimagelogtransferfunction
---

# CVImageLogTransferFunction

Identifies the specific log curve transfer function or gamma of the content.

## Declaration

```swift
enum CVImageLogTransferFunction
```

## Overview

Overview Log is a specific video format usually processed in a camera’s ISP. A Log video format usually defines: Scene-referred color primaries designed to preserve the chromaticity range captured by a camera sensor. In cinematography, “scene-referred” color primaries refers to a color space designed to accurately preserve the chromaticity and dynamic range directly captured by a camera sensor. A specific gamma curve (or transfer characteristic) tailored to capturing the full dynamic range from the sensor. This gamma curve is usually shaped like a log curve (hence the name Log). A set of matrix transforms to go from RGB to Y’CbCr (Y’CbCr being the most common format used to store the bits compressed into a file). As described above, a Log video format defines a whole color space (even though the “log” part of the name comes only from the “transfer characteristic” or gamma curve).

## Topics

### Enumeration Cases

- [CVImageLogTransferFunction.appleLog](corevideo/cvimagelogtransferfunction/applelog.md)
- [CVImageLogTransferFunction.appleLog2](corevideo/cvimagelogtransferfunction/applelog2.md)

## Relationships

### Conforms To

- [CVAttachmentValueRepresentable](corevideo/cvattachmentvaluerepresentable.md)
- [Copyable](swift/copyable.md)
- [Equatable](swift/equatable.md)
- [Escapable](swift/escapable.md)
- [Hashable](swift/hashable.md)
- [RawRepresentable](swift/rawrepresentable.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Color and signal characteristics

- [CVImageColorPrimaries](corevideo/cvimagecolorprimaries.md)
- [CVImageTransferFunction](corevideo/cvimagetransferfunction.md)
- [CVImageYCbCrMatrix](corevideo/cvimageycbcrmatrix.md)
- [CVImageAlphaChannelMode](corevideo/cvimagealphachannelmode.md)
- [CVImageFieldDetail](corevideo/cvimagefielddetail.md)