AVFoundation对焦模式iPad2

Question

我正试图在我的应用程序中进行自动对焦工作,在iPad2中进行测试.我的问题是,当我调用check方法时isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus,它总是返回NO.但是,我可以点击其他相机应用程序在我的设备中

devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
for (AVCaptureDevice *tempDevice in devices) {
    [tempDevice lockForConfiguration:nil];
    if ([tempDevice isFocusModeSupported:AVCaptureFocusModeAutoFocus]) {
        NSLog(@"Here");
    }

    if ([tempDevice isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus]) {
        NSLog(@"Here");
    }

    if ([tempDevice isFocusModeSupported:AVCaptureFocusModeLocked]) {
        NSLog(@"Here");
    }

    if ([tempDevice isFocusPointOfInterestSupported]) {
        NSLog(@"Here");
    }
    [tempDevice unlockForConfiguration];
}

Answer 1

我今晚只是在调查这个问题.根据我收集的内容,iPad 2不会进行对焦 - 它会进行曝光调整 - 因此在默认的相机应用程序中,点击屏幕会显示一个矩形,其中发生了点击,指示要进行白点调整的区域.

也许我错了,但这就是我所发现的,似乎已经通过你的API(isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus返回NO)测试得到证实.

iPad 2中的相机相当薄弱 - 尤其是前置相机.我很惊讶苹果发货了.

更新:这是更新的AVCamDemo Apple示例中的代码,用于处理焦点+曝光+白点.我不认为这是在AVCam示例中.AVCamDemo可以从开发人员中心下载WWDC代码.dmg软件包,而不是从网上下载.在我的iPad 2上,曝光代码永远不会被调用.// - 来自AVCamDemo:

- (BOOL) hasExposure
 {
AVCaptureDevice *device = [[self videoInput] device];

return  [device isExposureModeSupported:AVCaptureExposureModeLocked] ||
        [device isExposureModeSupported:AVCaptureExposureModeAutoExpose] ||
        [device isExposureModeSupported:AVCaptureExposureModeContinuousAutoExposure];
}

- (AVCaptureExposureMode) exposureMode
{
return [[[self videoInput] device] exposureMode];
}

- (void) setExposureMode:(AVCaptureExposureMode)exposureMode
{
if (exposureMode == 1) {
    exposureMode = 2;
}
AVCaptureDevice *device = [[self videoInput] device];
if ([device isExposureModeSupported:exposureMode] && [device exposureMode] != exposureMode) {
    NSError *error;
    if ([device lockForConfiguration:&error]) {
        [device setExposureMode:exposureMode];
        [device unlockForConfiguration];
    } else {
        id delegate = [self delegate];
        if ([delegate respondsToSelector:@selector(acquiringDeviceLockFailedWithError:)]) {
            [delegate acquiringDeviceLockFailedWithError:error];
        }
    }
}
}

- (BOOL) hasWhiteBalance
{
AVCaptureDevice *device = [[self videoInput] device];

return  [device isWhiteBalanceModeSupported:AVCaptureWhiteBalanceModeLocked] ||
        [device isWhiteBalanceModeSupported:AVCaptureWhiteBalanceModeAutoWhiteBalance];
}

- (AVCaptureWhiteBalanceMode) whiteBalanceMode
{
return [[[self videoInput] device] whiteBalanceMode];
}

- (void) setWhiteBalanceMode:(AVCaptureWhiteBalanceMode)whiteBalanceMode
{
if (whiteBalanceMode == 1) {
    whiteBalanceMode = 2;
}    
AVCaptureDevice *device = [[self videoInput] device];
if ([device isWhiteBalanceModeSupported:whiteBalanceMode] && [device whiteBalanceMode] != whiteBalanceMode) {
    NSError *error;
    if ([device lockForConfiguration:&error]) {
        [device setWhiteBalanceMode:whiteBalanceMode];
        [device unlockForConfiguration];
    } else {
        id delegate = [self delegate];
        if ([delegate respondsToSelector:@selector(acquiringDeviceLockFailedWithError:)]) {
            [delegate acquiringDeviceLockFailedWithError:error];
        }
    }
}
}

- (BOOL) hasFocus
{
AVCaptureDevice *device = [[self videoInput] device];

return  [device isFocusModeSupported:AVCaptureFocusModeLocked] ||
        [device isFocusModeSupported:AVCaptureFocusModeAutoFocus] ||
        [device isFocusModeSupported:AVCaptureFocusModeContinuousAutoFocus];
}

- (AVCaptureFocusMode) focusMode
{
return [[[self videoInput] device] focusMode];
}

- (void) setFocusMode:(AVCaptureFocusMode)focusMode
{


AVCaptureDevice *device = [[self videoInput] device];
if ([device isFocusModeSupported:focusMode] && [device focusMode] != focusMode) {
    NSError *error;

      printf(" setFocusMode    \n");
    if ([device lockForConfiguration:&error]) {
        [device setFocusMode:focusMode];
        [device unlockForConfiguration];
    } else {
        id delegate = [self delegate];
        if ([delegate respondsToSelector:@selector(acquiringDeviceLockFailedWithError:)]) {
            [delegate acquiringDeviceLockFailedWithError:error];
        }
    }    
}
}