Question

我有一个主视图控制器，它会转向第二个具有avcapturesession的视图控制器。我第一次从主视图控制器切换到捕获会话控制器，大约需要50ms（使用“仪器”检查）。然后我从捕获会话中回到主视图控制器，然后从主控制器返回到avcapturesession控制器。每次从主视图控制器切换到avcapturesession需要更长的时间，并且通过第5次或第6次迭代，segue需要大约10秒。（与第一次50ms相比。）我已经粘贴了下面的avcapture会话的相关代码。谁能帮忙解决这个问题？感谢

此类（NSObject类型）管理第二个视图控制器的捕获会话
实际上实现了avcapturesession

#import "CaptureSessionManager.h"

@implementation CaptureSessionManager

@synthesize captureSession;
@synthesize previewLayer;

#pragma mark Capture Session Configuration

- (id)init {
    if ((self = [super init])) {
        [self setCaptureSession:[[AVCaptureSession alloc] init]];
    }
    return self;
}

- (void)addVideoPreviewLayer {
    [self setPreviewLayer:[[[AVCaptureVideoPreviewLayer alloc] initWithSession:[self     captureSession]] autorelease]];
    [[self previewLayer] setVideoGravity:AVLayerVideoGravityResizeAspectFill];

}

- (void)addVideoInput {
        AVCaptureDevice *videoDevice = [AVCaptureDevice   defaultDeviceWithMediaType:AVMediaTypeVideo];
     if (videoDevice) {
         NSError *error;
        AVCaptureDeviceInput *videoIn = [AVCaptureDeviceInput  deviceInputWithDevice:videoDevice error:&error];
        if (!error) {
           if ([[self captureSession] canAddInput:videoIn])
               [[self captureSession] addInput:videoIn];

        //else
        //  NSLog(@"Couldn't add video input");
    }

//  else
    //  NSLog(@"Couldn't create video input");
}
//else
//  NSLog(@"Couldn't create video capture device");
}

- (void)dealloc {

    [[self captureSession] stopRunning];

    [previewLayer release], previewLayer = nil;
    [captureSession release], captureSession = nil;

    [super dealloc];
}

 @end

以下是avcapture视图控制器的viewdidLoad方法：

[self setCaptureManager:[[CaptureSessionManager alloc] init]]; 

[[self captureManager] addVideoInput];

[[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];

-(void)viewDidDisappear:(BOOL)animated{
    [super viewDidDisappear:YES];

    [[[self captureManager] previewLayer]removeFromSuperlayer];
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        [[captureManager captureSession] stopRunning];
    });

}

Memory allocation

Answer 1

我遇到同样的问题我发现这一行是主要问题

[[[self view] layer] addSublayer:[[self captureManager] previewLayer]];

在解除分配时，只需从超级层移除预览层，并且没有内存问题。我的解除分配功能如下

 -(void)deallocSession
{
[captureVideoPreviewLayer removeFromSuperlayer];
for(AVCaptureInput *input1 in session.inputs) {
    [session removeInput:input1];
}

for(AVCaptureOutput *output1 in session.outputs) {
    [session removeOutput:output1];
}
[session stopRunning];
session=nil;
outputSettings=nil;
device=nil;
input=nil;
captureVideoPreviewLayer=nil;
stillImageOutput=nil;
self.vImagePreview=nil;

}

我在弹出并推送任何其他视图之前调用了此函数。它解决了我的问题。

Answer 2

删除会话输入和输出似乎为我解决了这个问题

[captureSession stopRunning];
for(AVCaptureInput *input in captureSession.inputs) {
    [captureSession removeInput:input];
}

for(AVCaptureOutput *output in captureSession.outputs) {
    [captureSession removeOutput:output];
}

Answer 3

Swift版TUNER88的回答

func stopRecording() {
    captureSession.stopRunning()
    for input in captureSession.inputs {
        captureSession.removeInput(input)
    }
    for output in captureSession.outputs {
        captureSession.removeOutput(output)
    }
}

Answer 4

您似乎没有删除avcaptureViewController中的previewLayer，后者会在内部保留对捕获会话的引用。确保从该视图层次结构中删除了previewLayer。

Answer 5

Swift 3

    let session = AVCaptureSession()
    if let outputMovie = outputMovie, outputMovie.isRecording {
        outputMovie.stopRecording()
    }

    self.session.stopRunning()
    if let inputs = self.session.inputs as? [AVCaptureDeviceInput] {
        for input in inputs {
            self.session.removeInput(input)
        }
    }

    if let outputs = self.session.outputs as? [AVCaptureOutput] {
        for output in outputs {
            self.session.removeOutput(output)
        }
    }

Answer 6

对我有用的是将类型previewLayer的{{1}}设置为弱变量，然后在AVCaptureVideoPreviewLayer()函数中，我有：

stopCaptureSession()

事实证明，我所有的问题都连接到了PreviewLayer

Answer 7

这是TUNER88答案的快速版本

session.stopRunning()

    for(var i = 0 ; i < session.inputs.count ; i++){

        session.removeInput(session.inputs[i] as! AVCaptureInput)

    }

    for(var i = 0 ; i < session.outputs.count ; i++){

        session.removeOutput(session.outputs[i] as! AVCaptureOutput)

    }

会话重启后AVcapturesession启动缓慢

7 个答案: