AVCaptureDevice Class Reference

Inherits from
NSObject
Conforms to
NSObject (NSObject)
Framework
/System/Library/Frameworks/AVFoundation.framework
Availability
Available in iOS 4.0 and later.
Companion guide
AV Foundation Programming Guide
Declared in
AVCaptureDevice.h
Related sample code

Overview

An AVCaptureDevice object represents a physical capture device and the properties associated with that device. You use a capture device to configure the properties of the underlying hardware. A capture device also provides input data (such as audio or video) to an AVCaptureSession object.

You use the methods of the AVCaptureDevice class to enumerate the available devices, query their capabilities, and be informed about when devices come and go. Before you attempt to set properties of a capture device (its focus mode, exposure mode, and so on), you must first acquire a lock on the device using the lockForConfiguration: method. You can then set the properties and release the lock using the unlockForConfiguration method. You may hold the lock if you want all settable device properties to remain unchanged. However, holding the device lock unnecessarily may degrade capture quality in other applications sharing the device and is not recommended.

Tasks

Discovering Devices

Managing the Device’s Configuration

Focus Settings

Exposure Settings

White Balance Settings

Managing Flash Settings

Managing Torch Settings

Managing Low Light Settings

Monitoring Subject Area Change

Device Characteristics

Properties

adjustingExposure

Indicates whether the device is currently adjusting its exposure setting. (read-only)

@property(nonatomic, readonly, getter=isAdjustingExposure) BOOL adjustingExposure
Discussion

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

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

adjustingFocus

Indicates whether the device is currently adjusting its focus setting. (read-only)

@property(nonatomic, readonly, getter=isAdjustingFocus) BOOL adjustingFocus
Discussion

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

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

adjustingWhiteBalance

Indicates whether the devise is currently adjusting the white balance. (read-only)

@property(nonatomic, readonly, getter=isAdjustingWhiteBalance) BOOL adjustingWhiteBalance
Discussion

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

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

automaticallyEnablesLowLightBoostWhenAvailable

A Boolean value that indicates whether the capture device should automatically switch to low light boost mode when necessary.

@property(nonatomic) BOOL automaticallyEnablesLowLightBoostWhenAvailable
Discussion

On an AVCaptureDevice object where lowLightBoostSupported is YES, a special low light boost mode may be engaged to improve image quality. When the automaticallyEnablesLowLightBoostWhenAvailable property is set to YES, the capture device switches at its discretion to a special boost mode under low light. When the scene becomes sufficiently lit, the device switches back to normal operation. An AVCaptureDevice that supports this feature may only engage boost mode for certain source formats or resolutions.

The default value of this property is NO. Setting this property throws an NSInvalidArgumentException if lowLightBoostSupported is NO. The AVCaptureDevice object must be locked for configuration using lockForConfiguration: before clients can set this method, otherwise an NSGenericException is thrown.

Clients may observe changes to the lowLightBoostEnabled property using key-value observing to know when the boost mode engages. The switch between normal operation and low light boost mode may drop one or more video frames.

Availability
  • Available in iOS 6.0 and later.
Declared In
AVCaptureDevice.h

connected

Indicates whether the device is currently connected. (read-only)

@property(nonatomic, readonly, getter=isConnected) BOOL connected
Discussion

The value of this property indicates whether the device represented by the receiver is connected and available for use as a capture device. When the value of this property becomes NO for a given instance, however, it will not become YES again. If the same physical device again becomes available to the system, it will be represented using a new instance of AVCaptureDevice.

You can observe the value of this property using key-value observing to be notified when a device is no longer available.

Availability
  • Available in iOS 4.0 and later.
Related Sample Code
Declared In
AVCaptureDevice.h

exposureMode

The exposure mode for the device.

@property(nonatomic) AVCaptureExposureMode exposureMode
Discussion

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, setting the value of this property raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

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

See “AVCaptureExposureMode” for possible values.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

exposurePointOfInterest

The point of interest for exposure.

@property(nonatomic) CGPoint exposurePointOfInterest
Discussion

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, setting the value of this property raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

exposurePointOfInterestSupported

Indicates whether the device supports a point of interest for exposure. (read-only)

@property(nonatomic, readonly, getter=isExposurePointOfInterestSupported) BOOL exposurePointOfInterestSupported
Discussion

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

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

flashActive

Indicates whether the flash is currently active. (read-only)

@property(nonatomic, readonly, getter=isFlashActive) BOOL flashActive
Discussion

When the flash is active, it will flash if a still image is captured.

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

Availability
  • Available in iOS 5.0 and later.
See Also
Declared In
AVCaptureDevice.h

flashAvailable

Indicates whether the flash is currently available for use. (read-only)

@property(nonatomic, readonly, getter=isFlashAvailable) BOOL flashAvailable
Discussion

The flash may become unavailable if, for example, the device overheats and needs to cool off.

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

Availability
  • Available in iOS 5.0 and later.
See Also
Declared In
AVCaptureDevice.h

flashMode

The current flash mode.

@property(nonatomic) AVCaptureFlashMode flashMode
Discussion

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, setting the value of this property raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

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

See “AVCaptureFlashMode” for possible values.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

focusMode

The device’s focus mode.

@property(nonatomic) AVCaptureFocusMode focusMode
Discussion

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, setting the value of this property raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

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

See “AVCaptureFocusMode” for possible values.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

focusPointOfInterest

The point of interest for focusing.

@property(nonatomic) CGPoint focusPointOfInterest
Discussion

This property represents a CGPoint where {0,0} corresponds to the top left of the picture area, and {1,1} corresponds to the bottom right in landscape mode with the home button on the right—this applies even if the device is in portrait mode.

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, setting the value of this property raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

focusPointOfInterestSupported

Indicates whether the device supports a point of interest for focus. (read-only)

@property(nonatomic, readonly, getter=isFocusPointOfInterestSupported) BOOL focusPointOfInterestSupported
Discussion

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

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

hasFlash

Indicates whether the capture device has a flash. (read-only)

@property(nonatomic, readonly) BOOL hasFlash
Discussion

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

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

hasTorch

A Boolean value that specifies whether the capture device has a torch. (read-only)

@property(nonatomic, readonly) BOOL hasTorch
Discussion

A torch is a light source, such as an LED flash, that is available on the device and used for illuminating captured content or providing general illumination. This property reflects whether the current device has such illumination hardware built-in.

Even if the device has a torch, that torch might not be available for use. Thus, you should also check the value of the torchAvailable property before using it.

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

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

localizedName

A localized human-readable name for the receiver. (read-only)

@property(nonatomic, readonly) NSString *localizedName
Discussion

You can use this property to display the name of a capture device in a user interface.

Availability
  • Available in iOS 4.0 and later.
See Also
Related Sample Code
Declared In
AVCaptureDevice.h

lowLightBoostEnabled

A Boolean value that indicates whether the capture device’s low light boost feature is enabled. (read-only)

@property(nonatomic, readonly, getter=isLowLightBoostEnabled) BOOL lowLightBoostEnabled
Discussion

The value of this property indicates whether the AVCaptureDevice object is currently enhancing images to improve quality due to low light conditions. When this property is YES, the capture device has switched into a special mode in which more light can be perceived in images.

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

Availability
  • Available in iOS 6.0 and later.
See Also
Declared In
AVCaptureDevice.h

lowLightBoostSupported

A Boolean value that indicates whether the capture device supports boosting images in low light conditions. (read-only)

@property(nonatomic, readonly, getter=isLowLightBoostSupported) BOOL lowLightBoostSupported
Discussion

The AVCaptureDevice object’s automaticallyEnablesLowLightBoostWhenAvailable property can only be set if this property is YES.

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

Availability
  • Available in iOS 6.0 and later.
See Also
Declared In
AVCaptureDevice.h

modelID

The model ID of the device. (read-only)

@property(nonatomic, readonly) NSString *modelID
Discussion

The value of this property is an identifier unique to all devices of the same model. The value is persistent across device connections and disconnections, and across different systems. For example, the model ID of the camera built in to two identical iPhone models will be the same even though they are different physical devices.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

position

Indicates the physical position of the device hardware on the system. (read-only)

@property(nonatomic, readonly) AVCaptureDevicePosition position
Discussion

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

See “AVCaptureDevicePosition” for possible values.

Availability
  • Available in iOS 4.0 and later.
Related Sample Code
Declared In
AVCaptureDevice.h

subjectAreaChangeMonitoringEnabled

Indicates whether the device should monitor the subject area for changes.

@property(nonatomic, getter=isSubjectAreaChangeMonitoringEnabled) BOOL subjectAreaChangeMonitoringEnabled
Discussion

The value of this property indicates whether the receiver should monitor the video subject area for changes, such as lighting changes, substantial movement, and so on. If subject area change monitoring is enabled, the capture device object sends an AVCaptureDeviceSubjectAreaDidChangeNotification whenever it detects a change to the subject area, at which time an interested client may wish to re-focus, adjust exposure, white balance, etc.

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, setting the value of this property raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

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

Availability
  • Available in iOS 5.0 and later.
See Also
Declared In
AVCaptureDevice.h

torchActive

A Boolean value indicating whether the device’s torch is currently active. (read-only)

@property(nonatomic, readonly, getter=isTorchActive) BOOL torchActive
Discussion

A torch must be present on the device and currently available before it can be active.

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

Availability
  • Available in iOS 6.0 and later.
Declared In
AVCaptureDevice.h

torchAvailable

Indicates whether the torch is currently available for use. (read-only)

@property(nonatomic, readonly, getter=isTorchAvailable) BOOL torchAvailable
Discussion

The torch may become unavailable if, for example, the device overheats and needs to cool off.

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

Availability
  • Available in iOS 5.0 and later.
See Also
Declared In
AVCaptureDevice.h

torchLevel

The current torch brightness level. (read-only)

@property(nonatomic, readonly) float torchLevel
Discussion

The value of this property is a floating-point number whose value is in the range 0.0 to 1.0. A torch level of 0.0 indicates that the torch is off. A torch level of 1.0 represents the theoretical maximum value, although the actual maximum value may be lower if the device is currently overheated.

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

Availability
  • Available in iOS 5.0 and later.
See Also
Declared In
AVCaptureDevice.h

torchMode

The current torch mode.

@property(nonatomic) AVCaptureTorchMode torchMode
Discussion

Setting the value of this property also sets the torch level to its maximum current value.

Before setting the value of this property, call the isTorchModeSupported: method to make sure the device supports the desired mode. Setting the device to an unsupported torch mode results in the raising of an exception. For a list of possible values for this property, see “AVCaptureTorchMode.”

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, setting the value of this property raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

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

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

uniqueID

An ID unique to the model of device corresponding to the receiver. (read-only)

@property(nonatomic, readonly) NSString *uniqueID
Discussion

Every available capture device has a unique ID that persists on one system across device connections and disconnections, application restarts, and reboots of the system itself. You can store the value returned by this property to recall or track the status of a specific device in the future.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

whiteBalanceMode

The current white balance mode.

@property(nonatomic) AVCaptureWhiteBalanceMode whiteBalanceMode
Discussion

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, setting the value of this property raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

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

See “AVCaptureWhiteBalanceMode” for possible values.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

Class Methods

defaultDeviceWithMediaType:

Returns the default device used to capture data of a given media type.

+ (AVCaptureDevice *)defaultDeviceWithMediaType:(NSString *)mediaType
Parameters
mediaType

A media type identifier.

For possible values, see AV Foundation Constants Reference.

Return Value

The default device used to capture data of the type indicated by mediaType.

Availability
  • Available in iOS 4.0 and later.
Related Sample Code
Declared In
AVCaptureDevice.h

devices

Returns an array of the available capture devices on the system.

+ (NSArray *)devices
Return Value

An array containing the available capture devices on the system

Availability
  • Available in iOS 4.0 and later.
Declared In
AVCaptureDevice.h

devicesWithMediaType:

Returns an array of the devices able to capture data of a given media type.

+ (NSArray *)devicesWithMediaType:(NSString *)mediaType
Parameters
mediaType

A media type identifier.

For possible values, see AV Foundation Constants Reference.

Return Value

An array containing the devices able to capture data of the type indicated by mediaType.

Availability
  • Available in iOS 4.0 and later.
Related Sample Code
Declared In
AVCaptureDevice.h

deviceWithUniqueID:

Returns the device with a given ID.

+ (AVCaptureDevice *)deviceWithUniqueID:(NSString *)deviceUniqueID
Parameters
deviceUniqueID

The ID of a capture device.

Return Value

The device with ID deviceUniqueID.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

Instance Methods

hasMediaType:

Returns a Boolean value that indicates whether the device provides media with a given type.

- (BOOL)hasMediaType:(NSString *)mediaType
Parameters
mediaType

A media type, such as AVMediaTypeVideo, AVMediaTypeAudio, or AVMediaTypeMuxed. For a complete list of supported media type constants, see AV Foundation Constants Reference.

Return Value

YES if the device provides media of type mediaType, otherwise NO.

Availability
  • Available in iOS 4.0 and later.
Declared In
AVCaptureDevice.h

isExposureModeSupported:

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

- (BOOL)isExposureModeSupported:(AVCaptureExposureMode)exposureMode
Parameters
exposureMode

An exposure mode. See “AVCaptureExposureMode” for possible values.

Return Value

YES if exposureMode is supported, otherwise NO.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

isFlashModeSupported:

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

- (BOOL)isFlashModeSupported:(AVCaptureFlashMode)flashMode
Parameters
flashMode

A flash mode. See “AVCaptureFlashMode” for possible values.

Return Value

YES if flashMode is supported, otherwise NO.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

isFocusModeSupported:

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

- (BOOL)isFocusModeSupported:(AVCaptureFocusMode)focusMode
Parameters
focusMode

A focus mode. See “AVCaptureFocusMode” for possible values.

Return Value

YES if focusMode is supported, otherwise NO.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

isTorchModeSupported:

Returns a Boolean value that indicates whether the device supports the specified torch mode.

- (BOOL)isTorchModeSupported:(AVCaptureTorchMode)torchMode
Parameters
torchMode

The desired torch mode. For a list of possible values, see “AVCaptureTorchMode.”

Return Value

YES if torchMode is supported, otherwise NO.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

isWhiteBalanceModeSupported:

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

- (BOOL)isWhiteBalanceModeSupported:(AVCaptureWhiteBalanceMode)whiteBalanceMode
Parameters
whiteBalanceMode

A focus mode. See “AVCaptureWhiteBalanceMode” for possible values.

Return Value

YES if whiteBalanceMode is supported, otherwise NO.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

lockForConfiguration:

Requests exclusive access to the device’s hardware properties.

- (BOOL)lockForConfiguration:(NSError **)outError
Parameters
outError

On input, specify a pointer to an error object. If a lock cannot be acquired, this pointer contains an NSError object that describes the problem. You may specify nil for this property.

Return Value

YES if a lock was acquired or NO if it was not.

Discussion

You must call this method before attempting to configure the hardware related properties of the device. This method returns YES when it successfully locks the device for configuration by your code. After configuring the device properties, call unlockForConfiguration to release the configuration lock and allow other apps to make changes.

You may hold onto a lock (instead of releasing it) if you require the device properties to remain unchanged. However, holding the device lock unnecessarily may degrade capture quality in other apps sharing the device.

Availability
  • Available in iOS 4.0 and later.
See Also
Declared In
AVCaptureDevice.h

setTorchModeOnWithLevel:error:

Sets the illumination level when in torch mode.

- (BOOL)setTorchModeOnWithLevel:(float)torchLevel error:(NSError **)outError
Parameters
torchLevel

The new torch mode level. This value must be a floating-point number between 0.0 and 1.0. To set the torch mode level to the currently available maximum, specify the constant AVCaptureMaxAvailableTorchLevel for this parameter.

outError

On input, a pointer to an error object. If an error occurs, this method assigns an error object to the pointer with information about what happened.

Return Value

YES if the torch mode level was set or NO if it was not.

Discussion

This method sets the torch mode to AVCaptureTorchModeOn and sets the level to the specified value. If the device does not support the AVCaptureTorchModeOn torch mode or if you specify a value for torchLevel that is outside the accepted range, this method throws an exception. If the torch value in is within the accepted range but greater than the currently supported maximum—perhaps because the device is overheating—this method simply returns NO.

Before changing the value of this property, you must call lockForConfiguration: to acquire exclusive access to the device’s configuration properties. If you do not, this method raises an exception. When you are done configuring the device, call unlockForConfiguration to release the lock and allow other devices to configure the settings.

Availability
  • Available in iOS 6.0 and later.
Declared In
AVCaptureDevice.h

supportsAVCaptureSessionPreset:

Returns a Boolean value that indicates whether the receiver can be used in an capture session configured with the given preset.

- (BOOL)supportsAVCaptureSessionPreset:(NSString *)preset
Parameters
preset

A capture session preset.

Return Value

YES if the receiver can be used with preset, otherwise NO.

Discussion

An AVCaptureSession instance can be associated with a preset that configures its inputs and outputs to fulfill common use cases. You can use this method to determine if the receiver can be used in a capture session with the given preset. For a list of preset constants, see AVCaptureSession Class Reference.

Availability
  • Available in iOS 4.0 and later.
Declared In
AVCaptureDevice.h

unlockForConfiguration

Relinquishes exclusive control over the device’s configuration.

- (void)unlockForConfiguration
Discussion

Call this method to release the lock acquired using the lockForConfiguration: method when you are done configuring the device.

Availability
  • Available in iOS 4.0 and later.
See Also
Related Sample Code
Declared In
AVCaptureDevice.h

Constants

AVCaptureDevicePosition

Constants to specify the position of a capture device.

enum {
   AVCaptureDevicePositionUnspecified = 0,
   AVCaptureDevicePositionBack  = 1,
   AVCaptureDevicePositionFront = 2
};
typedef NSInteger AVCaptureDevicePosition;
Constants
AVCaptureDevicePositionUnspecified

The capture device’s position relative to the system hardware is unspecified.

Available in iOS 6.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureDevicePositionBack

The capture device is on the back of the unit.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureDevicePositionFront

The capture device is on the front of the unit.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureFlashMode

Constants to specify the flash mode of a capture device.

enum {
   AVCaptureFlashModeOff    = 0,
   AVCaptureFlashModeOn     = 1,
   AVCaptureFlashModeAuto   = 2
};
typedef NSInteger AVCaptureFlashMode;
Constants
AVCaptureFlashModeOff

The capture device flash is always off.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureFlashModeOn

The capture device flash is always on.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureFlashModeAuto

The capture device continuously monitors light levels and uses the flash when necessary.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureTorchMode

Constants to specify the direction in which a capture device faces

enum {
   AVCaptureTorchModeOff    = 0,
   AVCaptureTorchModeOn     = 1,
   AVCaptureTorchModeAuto   = 2
};
typedef NSInteger AVCaptureTorchMode;
Constants
AVCaptureTorchModeOff

The capture device torch is always off.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureTorchModeOn

The capture device torch is always on.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureTorchModeAuto

The capture device continuously monitors light levels and uses the torch when necessary.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

Torch Level Constant

The maximum torch level. 

const float AVCaptureMaxAvailableTorchLevel;
Constants
AVCaptureMaxAvailableTorchLevel

This constant always represents the maximum available torch level, independent of the actual maximum value currently supported by the device. Thus, pass this constant to the setTorchModeOnWithLevel:error: in situations where you want to specify the maximum torch level without having to worry about whether the device is overheating and might not accept a value of 1.0 as the maximum.

Available in iOS 6.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureFocusMode

Constants to specify the focus mode of a capture device.

enum {
   AVCaptureFocusModeLocked                = 0,
   AVCaptureFocusModeAutoFocus             = 1,
   AVCaptureFocusModeContinuousAutoFocus   = 2,
};
typedef NSInteger AVCaptureFocusMode;
Constants
AVCaptureFocusModeLocked

The focus is locked.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureFocusModeAutoFocus

The capture device performs an autofocus operation now.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureFocusModeContinuousAutoFocus

The capture device continuously monitors focus and auto focuses when necessary.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureExposureMode

Constants to specify the exposure mode of a capture device.

enum {
   AVCaptureExposureModeLocked                    = 0,
   AVCaptureExposureModeAutoExpose                = 1,
   AVCaptureExposureModeContinuousAutoExposure    = 2,
};
typedef NSInteger AVCaptureExposureMode;
Constants
AVCaptureExposureModeLocked

The exposure setting is locked.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureExposureModeAutoExpose

The device performs an auto-expose operation now.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureExposureModeContinuousAutoExposure

The device continuously monitors exposure levels and auto exposes when necessary.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureWhiteBalanceMode

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

enum {
   AVCaptureWhiteBalanceModeLocked             = 0,
   AVCaptureWhiteBalanceModeAutoWhiteBalance   = 1,
   AVCaptureWhiteBalanceModeContinuousAutoWhiteBalance = 2,
};
typedef NSInteger AVCaptureWhiteBalanceMode;
Constants
AVCaptureWhiteBalanceModeLocked

The white balance setting is locked.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureWhiteBalanceModeAutoWhiteBalance

The device performs an auto white balance operation now.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

AVCaptureWhiteBalanceModeContinuousAutoWhiteBalance

The device continuously monitors white balance and adjusts when necessary.

Available in iOS 4.0 and later.

Declared in AVCaptureDevice.h.

Notifications

AVCaptureDeviceWasConnectedNotification

Notification that is posted when a new device becomes available.
Availability
Declared In
AVCaptureDevice.h

AVCaptureDeviceWasDisconnectedNotification

Notification that is posted when an existing device becomes unavailable.
Availability
Declared In
AVCaptureDevice.h

AVCaptureDeviceSubjectAreaDidChangeNotification

Notification that is posted when the instance of AVCaptureDevice has detected a substantial change to the video subject area.

This notification is only sent if you first set subjectAreaChangeMonitoringEnabled to YES.

Availability
Declared In
AVCaptureDevice.h


© 2012 Apple Inc. All Rights Reserved. (Last updated: 2012-12-13)

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