当我开始在NSInvalidArgumentException中录制视频但仅在以前的视图控制器中拍摄照片后，我偶尔会遇到viewController异常。我已尝试过Google及其他几项建议，但仍然会在startRecordingToOutputFileURL:fileURL来电时收到此错误。
如果我没有访问拍摄照片的其他视图控制器，我从未收到错误 - 只有在我拍照时才会出现，然后切换到进行视频录制的新视图控制器。
我认为拍照留下了一些遗留问题，但是当我初始化录像机视图控制器时，我没有错误设置会话等等。有什么想法或如何从中恢复？为什么它是NSInvalidArgumentException例外？谢谢！
这是我的代码：
dispatch_async(dispatch_get_main_queue(), ^{
// Try to Fix bug:
// http://stackoverflow.com/questions/5979962/error-while-recording-video-on-iphone-using-avfoundation
[self.captureSession beginConfiguration];
// Ensure session is running
if ( [self.captureSession isRunning] == NO ) {
NSLog(@"Capture session is NOT running... Starting it now!");
[self.captureSession startRunning];
}
else {
NSLog(@"Capture session is ALREADY running...");
}
NSLog(@"File URL is: %@",fileURL);
NSLog(@"FileOutput is: %@",self.fileOutput);
[self.fileOutput startRecordingToOutputFileURL:fileURL recordingDelegate:self];
// Try to Fix bug:
// http://stackoverflow.com/questions/5979962/error-while-recording-video-on-iphone-using-avfoundation
[self.captureSession commitConfiguration];
});
以下是错误追溯：
2014-05-18 16:01:38.818 app[1699:60b] *** Start recording
2014-05-18 16:01:38.820 app[1699:60b] Capture session is ALREADY running...
2014-05-18 16:01:38.827 app[1699:60b] Capture session is ALREADY running...
2014-05-18 16:01:38.828 app[1699:60b] File URL is: file:////var/mobile/Applications/73FFC590-05A8-4D74-82D9-EBA122B00A20/Documents/2014-05-18-16-01-38-0.mp4
2014-05-18 16:01:38.828 app[1699:60b] FileOutput is: <AVCaptureMovieFileOutput: 0x16513b10>
2014-05-18 16:01:38.829 app[1699:60b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[AVCaptureMovieFileOutput startRecordingToOutputFileURL:recordingDelegate:] - no active/enabled connections.'
*** First throw call stack:
(0x2fe5ff0b 0x3a5f6ce7 0x2ed5751d 0xfb4b5 0x3aadfd53 0x3aadfd3f 0x3aae26c3 0x2fe2a681 0x2fe28f4d 0x2fd93769 0x2fd9354b 0x34d006d3 0x326f2891 0xe40c9 0x3aaf4ab7)
libc++abi.dylib: terminating with uncaught exception of type NSException
这就是captureSession的初始化方式（来自这里的OpenSource项目：https://github.com/shu223/SlowMotionVideoRecorder）：
- (id)initWithPreviewView:(UIView *)previewView {
self = [super init];
if (self) {
NSError *error;
self.captureSession = [[AVCaptureSession alloc] init];
self.captureSession.sessionPreset = AVCaptureSessionPresetInputPriority;
AVCaptureDevice *videoDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
AVCaptureDeviceInput *videoIn = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:&error];
if (error) {
NSLog(@"Video input creation failed");
return nil;
}
if (![self.captureSession canAddInput:videoIn]) {
NSLog(@"Video input add-to-session failed");
return nil;
}
[self.captureSession addInput:videoIn];
// save the default format
self.defaultFormat = videoDevice.activeFormat;
defaultVideoMaxFrameDuration = videoDevice.activeVideoMaxFrameDuration;
AVCaptureDevice *audioDevice= [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];
AVCaptureDeviceInput *audioIn = [AVCaptureDeviceInput deviceInputWithDevice:audioDevice error:&error];
[self.captureSession addInput:audioIn];
self.fileOutput = [[AVCaptureMovieFileOutput alloc] init];
[self.captureSession addOutput:self.fileOutput];
self.previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:self.captureSession];
self.previewLayer.frame = previewView.bounds;
self.previewLayer.contentsGravity = kCAGravityResizeAspectFill;
self.previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
[previewView.layer insertSublayer:self.previewLayer atIndex:0];
[self.captureSession startRunning];
}
return self;
}
我的代码在viewDidLoad中使用了这样的初始化代码：
self.captureManager = [[AVCaptureManager alloc] initWithPreviewView:self.view];
self.captureManager.delegate = self;
实际开始和停止录制的代码是从IBAction方法完成的，如下所示：
- (IBAction)recButtonTapped:(id)sender {
// REC START
if (self.captureManager.isRecording == NO ) {
NSLog(@"*** Start recording");
// change UI
[self.recBtn setImage:self.recStopImage
forState:UIControlStateNormal];
self.fpsControl.enabled = NO;
// timer start
startTime = [[NSDate date] timeIntervalSince1970];
self.timer = [NSTimer scheduledTimerWithTimeInterval:0.01
target:self
selector:@selector(timerHandler:)
userInfo:nil
repeats:YES];
[self.captureManager startRecording];
}
// REC STOP
else {
NSLog(@"*** Stop recording");
isNeededToSave = YES;
[self.captureManager stopRecording];
[self.timer invalidate];
self.timer = nil;
// change UI
[self.recBtn setImage:self.recStartImage
forState:UIControlStateNormal];
self.fpsControl.enabled = YES;
}
}
编辑 - 我肯定在Photo视图中关闭会话，这是代码。我确认在离开Photo View控制器时正在调用它。
NSLog(@"RELEASE PHOTO SESSION NOW!");
for(AVCaptureInput *input1 in _mySesh.inputs) {
[_mySesh removeInput:input1];
}
for(AVCaptureOutput *output1 in _mySesh.outputs) {
[_mySesh removeOutput:output1];
}
[_mySesh stopRunning];
// Fix closing of session
dispatch_after(
dispatch_time(0,500000000),
dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0),
^{
_mySesh = nil;
}
);
根据下面的唯一答案，我尝试在开始录制之前“取消链接”文件。它仍然无效。
NSURL *fileURL = [NSURL URLWithString:[@"file://" stringByAppendingString:filePath]];
//NSLog(@"Beginning to record to output file...");
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), ^{
// Wait for session to start
//[NSThread sleepForTimeInterval:1.0];
dispatch_async(dispatch_get_main_queue(), ^{
// Ensure session is running
if ( [self.captureSession isRunning] == NO ) {
NSLog(@"Capture session is NOT running... Starting it now!");
[self.captureSession startRunning];
}
else {
NSLog(@"Capture session is ALREADY running...");
}
NSLog(@"File URL is: %@",fileURL);
NSLog(@"FileOutput is: %@",self.fileOutput);
// Delete the file
unlink([[@"file://" stringByAppendingString:filePath] UTF8String]);
[self.fileOutput startRecordingToOutputFileURL:fileURL recordingDelegate:self];
});
});
对于后代，我称之为'didFinishRecordingToOutputFileAtURL'委托方法：
- (void) captureOutput:(AVCaptureFileOutput *)captureOutput
didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL
fromConnections:(NSArray *)connections error:(NSError *)error
{
// Print any errors
if ( error ) {
NSLog(@"Error Recording Video! %@",error.localizedDescription);
}
_isRecording = NO;
if ([self.delegate respondsToSelector:@selector(didFinishRecordingToOutputFileAtURL:error:)]) {
[self.delegate didFinishRecordingToOutputFileAtURL:outputFileURL error:error];
}
}
答案 0 :(得分：4)
首先，首先启动AVCaptureSession。之后，您可以创建AVPreviewLayer和AVCaptureMovieFileOutput。
其次，在向捕获会话添加任何内容之前使用-[AVCaptureSession canAddOutput:]和-[AVCaptureSession canAddInput:]，这将为您节省大量时间和挫折。
第三，当您想要立即更改captureSession中的大量内容时，您只需要beginConfiguration和commitConfiguration，例如删除输入，更改预设。如果您要实现它，它在前/后摄像头开关上很有用。在这些调用之间启动或停止会话绝不是简单的。
答案 1 :(得分：2)
据我所知，这是由于该文件已经存在。
尝试在致电startRecordingToOutputFileURL:之前删除该文件：
[[NSFileManager defaultManager] removeItemAtPath:fileURL];
您可以仔细检查：
[[NSFileManager defaultManager] fileExistsAtPath:fileURL];
If a file at the given URL already exists when capturing starts, recording to the new file will fail.
可能导致崩溃的另一件事是，如果您没有实施委托方法。
需要实施：
captureOutput:didFinishRecordingToOutputFileAtURL:fromConnections:error:
因为这是获得输出的唯一可靠的地方。
另一个可疑的事情：
创建fileURL时，您可以
NSURL *fileURL = [NSURL URLWithString:[@"file://" stringByAppendingString:filePath]];
可以将其更改为
NSURL *fileURL = [NSURL fileURLWithPath:filePath];
确保filePath有效。
来自文档：This method throws an NSInvalidArgumentException if the URL is not a valid file URL.
答案 2 :(得分：0)
尝试评论self.captureSession.sessionPreset = ...行，看看是否有帮助。它成了我的伎俩。问题的原因是我试图捕获具有最高质量和FOV的照片，但是当我尝试捕获视频时，我在这个设置中得到“没有活动/启用连接”异常。
答案 3 :(得分：0)
只需将sessionPreset设置为高。
迅捷4 self.captureSession.sessionPreset = .high