avfoundation

问题 So, I asked this question before on the Apple Developer Forums but never got a proper answer, so I thought I'd ask it here: I'm trying to make a simple game with a hit sound that has a different pitch whenever you hit something. I thought it'd be simple, but it ended up with a whole lot of stuff (most of which I completely copied from someone else): func hitSound(value: Float) { let audioPlayerNode = AVAudioPlayerNode() audioPlayerNode.stop() engine.stop() // This is an AVAudioEngine defined

问题 I am trying to play a video clip that loops indefinitely. I am doing this the way Apple recommends; by setting up a notification that gets triggered by AVPlayerItemDidPlayToEndTimeNotification: @property(nonatomic) AVPlayer *videoPlayer; @property(nonatomic) AVPlayerItem *videoPlayerItem; -(void)loadVideo { NSURL *url = [[NSBundle mainBundle] URLForResource:filename withExtension:extension]; AVURLAsset *asset = [AVURLAsset URLAssetWithURL:url options:nil]; NSString *tracksKey = @"tracks";

问题 This question already has answers here : App crashed in iOS 6 when user changes Contacts access permissions (2 answers) Closed 4 years ago . I have a collection view (standard flow layout) where the first cell is displaying a live camera feed, and the rest of the cells are displaying photos from the user's library using iOS 8's new Photos Framework. Everything renders and works great. When opening for the first time, I'm prompted for access to the Camera and to the Photos library, as expected

问题 I want to make the h.264 stream from server to a video file, but when I used assetwrite.finishwrite , the XCode reports Video /var/mobile/Applications/DE4196F1-BB77-4B7D-8C20-7A5D6223C64D/Documents/test.mov cannot be saved to the saved photos album: Error Domain=NSOSStatusErrorDomain Code=-12847 "This movie format is not supported." UserInfo=0x5334830 {NSLocalizedDescription=This movie format is not supported.}" Below is my code: data is the h.264 frame, just one frame, it might be i frame or

问题 I set up a video player using Player (using AVFoundation). I am trying to access and manipulate currentTime of the video however, the library is only providing duration of the video but not currentTime. I am tweaking the demo project of Player. Please check 'Updated' section below instead of here: A friend told me I can achieve using that approach, but I couldn't really get how to adapt this approach in this case. [NSTimer scheduledTimerWithInterval:1.0 target:self selector:@selector

问题 This line of code is the problem I got today (macOS app): NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]; After I update Xcode, the system is alway got me empty devices array. The thing is, the old projects(created before the update) work as expected. What's going on here...? Does anyone has the same problem? ------------UPDATE------------ I found this not just happened to my mac, also on the company's. And it does affect my work. 回答1: I think I found the answer...

问题 In my iPhone app,a user can record the video.I want to set the maximum allowed time of recording is to 30seconds.How to do that,any ideas ? using this code -(BOOL)startCameraControllerFromViewController:(UIViewController*)controller usingDelegate:(id )delegate { if (([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera] == NO) || (delegate == nil) || (controller == nil)) { return NO; } UIImagePickerController *cameraUI = [[UIImagePickerController alloc] init]

问题 I am trying to use AVVideoComposition to add some text on top of a video and save the video. This is the code I use: I Create an AVMutableComposition and AVVideoComposition var mutableComp = AVMutableComposition() var mutableVidComp = AVMutableVideoComposition() var compositionSize : CGSize? func configureAsset(){ let options = [AVURLAssetPreferPreciseDurationAndTimingKey : "true"] let videoAsset = AVURLAsset(url: Bundle.main.url(forResource: "Car", withExtension: "mp4")! , options : options)

问题 I'll start with a simple "playground" view controller class I've made that demonstrates my problem: class AudioEnginePlaygroundViewController: UIViewController { private var audioEngine: AVAudioEngine! private var micTapped = false override func viewDidLoad() { super.viewDidLoad() configureAudioSession() audioEngine = AVAudioEngine() } @IBAction func toggleMicTap(_ sender: Any) { guard let mic = audioEngine.inputNode else { return } if micTapped { mic.removeTap(onBus: 0) micTapped = false

问题 I am writing an app that automatically turns on the torch on the back of an iOS device depending on lighting conditions. The app renders a live camera view, and does not record the video. I have tried using AVCaptureTorchModeAuto , but it only seems to measure the brightness of the image at the start of the capture session, and set the torch accordingly. The setting then does not change afterwards, regardless of the brightness of the camera image. It is possible to have the system adjust the