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# CVImageLogTransferFunction

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

```
enum CVImageLogTransferFunction
```

## 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

[`case appleLog`](/documentation/CoreVideo/CVImageLogTransferFunction/appleLog)

Apple log profile.

[`case appleLog2`](/documentation/CoreVideo/CVImageLogTransferFunction/appleLog2)

Apple log 2 profile.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

[`Copyable`](/documentation/Swift/Copyable)

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

[`CVAttachmentValueRepresentable`](/documentation/CoreVideo/CVAttachmentValueRepresentable)

[`Escapable`](/documentation/Swift/Escapable)

---

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