AVCaptureVideoPreviewLayer running slower with time - ios

Question

I have a UIViewController where i set an AVCaptureVideoPreviewLayer on the init method to take pictures. When the photo is taken i dismiss the UIViewController.
Each time i open this UIViewController, the Ipad run slower until it crashes. I get a memory warning, so i think something its not being free, in the other hand, I am using ARC so i suppouse that each time i dismiss the UIViewController it frees the memory.
Here is the code on the init method of the UIViewController:
session = [[AVCaptureSession alloc] init];
session.sessionPreset = AVCaptureSessionPresetMedium;
AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
captureVideoPreviewLayer.affineTransform = CGAffineTransformMakeRotation(M_PI+M_PI_2);
captureVideoPreviewLayer.frame = CGRectMake(45, 55, 512, 387);
[self.cameraPlace.layer addSublayer:captureVideoPreviewLayer];
NSArray *cameras=[AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
AVCaptureDevice *device = [cameras objectAtIndex:1];
NSError *error = nil;
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];
[session addInput:input];
stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
NSDictionary *outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys: AVVideoCodecJPEG, AVVideoCodecKey, nil];
[stillImageOutput setOutputSettings:outputSettings];
[session addOutput:stillImageOutput];
[session startRunning];
Do i have something wrong? or do you have any clue?

Answer 1

I was having the same problem because I was adding a layer with a session that was already added.
self.captureVideoPreviewLayer = [AVCaptureVideoPreviewLayer
layerWithSession:self.session];
on the above line please set a breakpoint, you will observe it will take 3-4 seconds to proceed. Sometimes it creates a memory warning and sometimes it doesn't.
so just add check whether it is already added or not like below.
NSError *error;
[self.deviceCamera lockForConfiguration:&error];
if (self.session == nil)
{
self.session = [[AVCaptureSession alloc] init];
self.captureVideoPreviewLayer = [AVCaptureVideoPreviewLayer
layerWithSession:self.session];
CGRect screenBounds = [[UIScreen mainScreen]bounds];
self.captureVideoPreviewLayer.frame = screenBounds;
self.captureVideoPreviewLayer.videoGravity =
AVLayerVideoGravityResizeAspectFill; // to fill the camera fullscreen view
self.userInteractionEnabled = YES;
if ([self.session canAddInput:_input]) {
[self.session addInput:_input];
}
}
[self.session startRunning];
[self.layer addSublayer:self.captureVideoPreviewLayer];
if (self.stillImageOutput == nil)
{
self.stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
NSDictionary *outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys: AVVideoCodecJPEG, AVVideoCodecKey, nil];
[self.stillImageOutput setOutputSettings:outputSettings];
NSString* preset = 0;
if (!preset) {
preset = AVCaptureSessionPresetPhoto;
}
if ([self.session canSetSessionPreset:preset]) {
self.session.sessionPreset = preset;
}
if ([self.session canAddOutput:self.stillImageOutput]) {
[self.session addOutput:self.stillImageOutput];
}
}
objective-c ios avcapturesession