AVCaptureDevice iOS攝像頭屬性

AVCaptureDevice.h，主要用來獲取iphone一些關於相機設備的屬性。

AVCaptureDevice.h，必需要引入AVFoundation.framework包。

1. 前置和後置攝像頭
enum {
    AVCaptureDevicePositionBack = 1,
    AVCaptureDevicePositionFront = 2
};
typedef NSInteger AVCaptureDevicePosition;

2. 閃光燈開關
enum {
    AVCaptureFlashModeOff = 0,
    AVCaptureFlashModeOn = 1,
    AVCaptureFlashModeAuto = 2
};
typedef NSInteger AVCaptureFlashMode;

3. 手電筒開關
enum {
    AVCaptureTorchModelOff = 0,
    AVCaptureTorchModelOn = 1,
    AVCaptureTorchModeAuto = 2
};
typedef NSInteger AVCaptureTorchMode;

4. 焦距調整
enum {
    AVCaptureFocusModelLocked = 0,
    AVCaptureFocusModeAutoFocus = 1,
    AVCaptureFocusModeContinousAutoFocus = 2
};
typedef NSInteger AVCaptureFocusMode;

5. 曝光量調節
enum {
    AVCaptureExposureModeLocked = 0,
    AVCaptureExposureModeAutoExpose = 1,
    AVCaptureExposureModeContinuousAutoExposure = 2
};
typedef NSInteger AVCaptureExposureMode;

6. 白平衡
enum {
    AVCaptureWhiteBalanceModeLocked = 0,
    AVCaptureWhiteBalanceModeAutoWhiteBalance = 1,
    AVCaptureWhiteBalanceModeContinuousAutoWhiteBalance = 2
};
typedef NSInteger AVCaptureWhiteBalanceMode;