AVCamManual adds manual controls for focus, exposure, and white balance to the AVCam sample application.
iPhone 6 Plus shipped with a lens stabilization module that is used during still image capture to reduce the effects of hand-shake in low-light situations.
AVFoundation introduces an API to apply lens stabilization to still images captured via the bracketed capture APIs from iOS 8--this sample demonstrates the use of this API.
AVCamManual also uses size classes to work across all available sceen sizes.
To turn lens stabilization on during a bracketed still image capture sequence, first check if it's supported by querying the read-only property AVCaptureStillImageOutput.lensStabilizationDuringBracketedCaptureSupported. If it's supported, your code can then set AVCaptureStillImageOutput.lensStabilizationDuringBracketedCaptureEnabled to YES.
The property is "sticky" across still image captures. If the AVCaptureStillImageOutput.lensStabilizationDuringBracketedCaptureSupported ever switches to NO, AVCaptureStillImageOutput.lensStabilizationDuringBracketedCaptureEnabled will be forced off and will remain off even if lens stabilization becomes supported later. Both AVCaptureStillImageOutput.lensStabilizationDuringBracketedCaptureSupported and AVCaptureStillImageOutput.lensStabilizationDuringBracketedCaptureEnabled are KVO-able properties.
Applying lens stabilization will not always improve still image captures. It's most effective when exposure durations are greater than or equal to 1/30s. The motion or duration of capture may also exceed the amount of compensation the module is able to provide. To find out information about the stabilization applied to a given sample buffer of the bracket, examine the value of the CMSampleBuffer attachment key kCMSampleBufferAttachmentKey_StillImageLensStabilizationInfo:
CFStringRef lensStabilizationInfo = CMGetAttachment( sbuf, kCMSampleBufferAttachmentKey_StillImageLensStabilizationInfo, NULL /* attachmentModeOut */ );
The value will match one of the following strings:
kCMSampleBufferLensStabilizationInfo_Active: Stabilization was applied.kCMSampleBufferLensStabilizationInfo_OutOfRange: The motion couldn't be compensated for, or the capture duration exceeded the limits of the lens module.kCMSampleBufferLensStabilizationInfo_Unavailable: The module couldn't be used for this capture.kCMSampleBufferLensStabilizationInfo_Off: Lens stabilization wasn't requested for the bracketed capture.
Xcode 7, iOS 9 SDK
iOS 9.0
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