有没有办法在iPhone 4上手动设置iOS4中的低速静态相机设置,如快门速度,光圈或ISO？我不认为它存在于官方SDK中,但也许有人发现了一些私有API来允许这个？
我发现我的iPhone 4相机无法使用,因为即使在相当不错的光线下,它始终坚持以最慢的1/15秒快门速度拍摄,如果拍摄对象完全移动,会导致运动模糊.
谢谢!
我有一个程序来拍摄带有默认参数的视频,当我移动相机时,将自动调整曝光,聚焦和白平衡.我想在程序中添加2个按钮:LOCK和PRESET.按下LOCK按钮时,曝光,对焦和白平衡将被修复,其值将作为用户设置存储.PRESET按钮用于将用户设置设置为相机,以确保我们可以拍摄具有相同曝光,对焦和白平衡值的所有视频.
锁定部分很简单,我只需要改变模式,所以我想知道是否有任何方法可以获得并设置曝光,聚焦和白平衡的值.
以曝光为例,默认情况下,曝光模式设置为AVCaptureExposureModeContinuousAutoExposure,这意味着,当我拿着iPhone拍摄视频时,曝光将自动调整,以确保我们可以在明亮或黑暗的环境中清晰地看到场景.
AVCaptureDevice* pCaptureDevice = [self videoDeviceWithPosition:AVCaptureDevicePositionBack];
[pCaptureDevice lockForConfiguration:nil];
[pCaptureDevice setExposureMode:AVCaptureExposureModeContinuousAutoExposure];
[pCaptureDevice unlockForConfiguration];
按下LOCK按钮时,我将exposureMode更改为AVCaptureExposureModeLocked,因此不再更改当前曝光值.
[pCaptureDevice lockForConfiguration:nil];
[pCaptureDevice setExposureMode:AVCaptureExposureModeLocked];
[pCaptureDevice unlockForConfiguration];
但是,如何在按下按钮时获取曝光值？更重要的是,当按下PRESET时,如何将曝光值设置回AVCaptureDevice.
我在论坛中搜索过,只发现了Michael Grinich的帖子:访问iOS 6新的API,用于相机曝光和快门速度.我按照他的发现并尝试使用私有API获取并设置exposureGain和exposureDuration,但我发现在AVCaptureExposureModeContinuousAutoExposure模式下,当我将相机从黑暗环境移动到明亮时(曝光增益= 1.0和exposureDuration = {1,30,1,0}).设置它们并没有改变曝光度.
[pCaptureDevice lockForConfiguration:nil];
[pCaptureDevice setExposureMode:AVCaptureExposureModeLocked];
[pCaptureDevice setManualExposureSupportEnabled:YES];
NSLog(@"exposure gain: %f", [pCaptureDevice exposureGain]);
[pCaptureDevice setExposureGain:3.0];
NSLog(@"exposure gain: %f", [pCaptureDevice exposureGain]);
[pCaptureDevice unlockForConfiguration];
有人可以帮我解决这个问题吗？首先十分感谢!
后攻进行拍照,我要锁定曝光,一旦曝光,不再调整关闭的火炬.所以,我添加了一个观察者来处理adjustExposure:
- (IBAction)configureImageCapture:(id)sender
{
[self.session beginConfiguration];
[self.cameraController device:self.inputDevice exposureMode:AVCaptureExposureModeAutoExpose];
[self.cameraController device:self.inputDevice torchMode:AVCaptureTorchModeOn torchLevel:0.8f];
[self.session commitConfiguration];
[(AVCaptureDevice *)self.inputDevice addObserver:self forKeyPath:@"adjustingExposure" options:NSKeyValueObservingOptionNew context:MyAdjustingExposureObservationContext];
}
这是observeValueForKeyPath方法:
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
if (context == MyAdjustingExposureObservationContext) {
if( [keyPath isEqualToString:@"adjustingExposure"] )
{
BOOL adjustingExposure = [ [change objectForKey:NSKeyValueChangeNewKey] isEqualToNumber:[NSNumber numberWithInt:1] ];
if (!adjustingExposure)
{
[(AVCaptureDevice *)self.cameraController.inputDevice removeObserver:self forKeyPath:@"adjustingExposure"];
if ([self.inputDevice isExposureModeSupported:AVCaptureExposureModeLocked]) {
dispatch_async(dispatch_get_main_queue(),
^{
NSError *error = nil;
if ([self.inputDevice lockForConfiguration:&error]) {
// 5) lock the exposure
[self.cameraController device:self.inputDevice …我想控制 iPhone 的 ISO 和快门速度，但它在 AVFoundation 中没有 API。它只能改变曝光，wb for iphone。
如何控制 ISO 或快门速度？