在这里使用本教程:http://www.musicalgeometry.com/?p=1297 http://www.musicalgeometry.com/?p=1297我创建了一个自定义叠加层和图像捕获AVCaptureSession
.
我试图允许用户在前置摄像头和后置摄像头之间切换。这是我的代码CaptureSessionManager
切换相机:
- (void)addVideoInputFrontCamera:(BOOL)front {
NSArray *devices = [AVCaptureDevice devices];
AVCaptureDevice *frontCamera;
AVCaptureDevice *backCamera;
for (AVCaptureDevice *device in devices) {
//NSLog(@"Device name: %@", [device localizedName]);
if ([device hasMediaType:AVMediaTypeVideo]) {
if ([device position] == AVCaptureDevicePositionBack) {
//NSLog(@"Device position : back");
backCamera = device;
}
else {
//NSLog(@"Device position : front");
frontCamera = device;
}
}
}
NSError *error = nil;
if (front) {
AVCaptureDeviceInput *frontFacingCameraDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:frontCamera error:&error];
if (!error) {
if ([[self captureSession] canAddInput:frontFacingCameraDeviceInput]) {
[[self captureSession] addInput:frontFacingCameraDeviceInput];
} else {
NSLog(@"Couldn't add front facing video input");
}
}
} else {
AVCaptureDeviceInput *backFacingCameraDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:backCamera error:&error];
if (!error) {
if ([[self captureSession] canAddInput:backFacingCameraDeviceInput]) {
[[self captureSession] addInput:backFacingCameraDeviceInput];
} else {
NSLog(@"Couldn't add back facing video input");
}
}
}
}
现在,在我的自定义覆盖控制器中,我初始化了所有内容,如下所示viewDidLoad
:
[self setCaptureManager:[[CaptureSessionManager alloc] init]];
[[self captureManager] addVideoInputFrontCamera:NO]; // set to YES for Front Camera, No for Back camera
[[self captureManager] addStillImageOutput];
[[self captureManager] addVideoPreviewLayer];
CGRect layerRect = [[[self view] layer] bounds];
[[[self captureManager] previewLayer] setBounds:layerRect];
[[[self captureManager] previewLayer] setPosition:CGPointMake(CGRectGetMidX(layerRect),CGRectGetMidY(layerRect))];
[[[self view] layer] addSublayer:[[self captureManager] previewLayer]];
[[_captureManager captureSession] startRunning];
切换相机按钮连接到一个名为switchCamera
。我已经尝试过这个:
- (void)switchCameraView:(id)sender {
[[self captureManager] addVideoInputFrontCamera:YES]; // set to YES for Front Camera, No for Back camera
}
当调用这个时,我收到错误NSLog
来自CaptureSessionManager
我不明白为什么。在viewDidLoad
,如果我设置fontCamera
to YES
,显示前置摄像头但无法切换到后置摄像头,反之亦然。
关于如何让它正确切换有什么想法吗?