Instance Property

grayWorldDeviceWhiteBalanceGains

The current device-specific white balance values required for a neutral gray white point.

Declaration

@property(nonatomic, readonly) AVCaptureWhiteBalanceGains grayWorldDeviceWhiteBalanceGains;

Discussion

This property specifies the current red, green, and blue gain values derived from the current scene to deliver a neutral (or gray world) white point for white balance.

Gray world values assume a neutral subject (for example, a gray card) has been placed in the middle of the subject area and fills the center 50% of the frame. Clients can read these values and apply them to the device using setWhiteBalanceModeLockedWithDeviceWhiteBalanceGains:completionHandler:.

For each channel, only values between 1.0 and maxWhiteBalanceGain are supported. The value can be read at any time, regardless of white balance mode.

You can observe changes to the value of this property using Key-value observing.

See Also

Managing the White Balance

- isWhiteBalanceModeSupported:

Returns a Boolean value that indicates whether the given white balance mode is supported.

whiteBalanceMode

The current white balance mode.

adjustingWhiteBalance

Indicates whether the devise is currently adjusting the white balance.

- chromaticityValuesForDeviceWhiteBalanceGains:

Converts device-specific white balance RGB gain values to device-independent chromaticity values.

deviceWhiteBalanceGains

The current device-specific RGB white balance gain values.

maxWhiteBalanceGain

The maximum supported value to which a channel in the AVCaptureWhiteBalanceGains may be set.

- deviceWhiteBalanceGainsForChromaticityValues:

Converts device-independent chromaticity values to device-specific white balance RGB gain values.

- deviceWhiteBalanceGainsForTemperatureAndTintValues:

Converts device-independent temperature and tint values to device-specific white balance RGB gain values.

- setWhiteBalanceModeLockedWithDeviceWhiteBalanceGains:completionHandler:

Sets white balance to locked mode with the specified deviceWhiteBalanceGains values.

- temperatureAndTintValuesForDeviceWhiteBalanceGains:

Converts device-specific white balance RGB gain values to device-independent temperature and tint values.

lockingWhiteBalanceWithCustomDeviceGainsSupported

A Boolean value indicating whether the device supports locking white balance to specific gain values.

AVCaptureWhiteBalanceGainsCurrent

A special constant representing the current white balance setting.

AVCaptureWhiteBalanceGains

Structure containing RGB white balance gain values.

AVCaptureWhiteBalanceChromaticityValues

Structure containing CIE 1931 xy chromaticity values.

AVCaptureWhiteBalanceTemperatureAndTintValues

Structure containing temperature and tint values correlated to a white-balance color.

AVCaptureWhiteBalanceMode

Constants to specify the white balance mode of a capture device.