Discuss using the camera on Apple devices.

Posts under Camera tag

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CameraFrameProvider distortion correction
Hi, I'm trying to correct the lens distortion in frames provided by Enterprise API camera frame provider. The frames provided seem to have only in/extrinsics info, but not the distortion lookup table. Is there some magic setting, or function to do that (I can't seem to find anything like this)? Or is there a way to use AVCameraCalibrationData together with provider?
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371
Mar ’25
GameKit Access Point causes camera background image in ARKit to be black in iOS 18 beta only
I have an AR game using ARKit with SceneKit that works just fine in iOS 17. In the iOS 18 betas, the AR background image shows black instead of showing the real world. As a result there's no tracking and obviously the whole game is useless. I narrowed down the issue to showing the Game Center Access Point. My app has ViewController 1 (VC1) showing the main menu and that's where I want to show the GC Access Point. From there you open VC2 which shows a list of levels. Selecting any level will open VC3 which has the ARScene. Following is the code I use to start Game Center in VC1: GKLocalPlayer.local.authenticateHandler = { gcAuthVC, error in let isGameCenterReady = (gcAuthVC == nil) && (error == nil) if let viewController = gcAuthVC { self.present (viewController, animated: true, completion: nil) } if error != nil { print(error?.localizedDescription ?? "") } if isGameCenterReady { GKAccessPoint.shared.location = .topLeading GKAccessPoint.shared.showHighlights = true GKAccessPoint.shared.isActive = true } } When switching to VC2 I run GKAccessPoint.shared.isActive = false so that the Access Point will no longer show in any of the following VCs. I tried running it in VC1, VC2, and again in VC3 - it doesn't change anything. Once I reach VC3, the background is black. If in VC1 I don't run GKAccessPoint.shared.isActive = true, so I don't activate the access point, the behavior is as follows: If I wait until after the Game Center login animation completes and closes on its own and then I proceed to VC2 and VC3, the camera image will show correctly If I quickly move to VC2 before the Game Center login animation has completed, so my code will close it by setting active = false, and then I continue to VC3, I will see the black background problem. So it does look like activating the access point and then de-activating it causes the issue. BTW, if I activate the access point and leave it on in all VCs, the same black background issue persists. Other than that, when I'm in VC3 with the black background and I switch to another app (so my game moves to the background), when it returns to the foreground, the camera suddenly shows the real world correctly! I tried to manually reset the AR session by pausing and restarting it, but that didn't change anything. Also, when I check with the debugger, it looks like when the app comes back to the foreground it also doesn't run the session start code. But something does seem to reset itself so I wonder what that is. Maybe I could trigger the same manually in my cdoe??? I repeat that everything works just fine in iOS 17 and below. This problem only started with the iOS 18 beta (currently on beta 5, but it started in some of the previous betas as well). So could this be a bug in iOS 18? As a workaround I could check the iOS version and if it's iOS18 not activate the access point, hoping that the user will not jump to VC2 too quickly, and show my own button which will open Game Center. But I'd rather give the users the full experience with their own avatar and the highlights showing up. Plus, certainly some users will move quickly to VC2 and that will be an awful experience. Any help would be greatly appreciated. Thanks!
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1k
Mar ’25
iPhone 15 Pro Has USB-C, but AVCaptureDevice Doesn't Support External Devices?
I'm using an iPhone 15 Pro, which has switched from Lightning to USB Type-C. My iOS version is 18.3. According to Apple's documentation, AVCaptureDevice.DeviceType should support external device types. 🔗 Apple's Official Documentation: https://developer.apple.com/documentation/avfoundation/avcapturedevice/devicetype-swift.struct/external The documentation clearly states that iPadOS 17.0+ and iOS 17.0+ support external devices. However, in my actual tests: On iPhone, discoverySession does not detect any external devices. On iPad, discoverySession can detect external devices without any issues. My Question: Does iPhone USB-C actually support external devices (e.g., UVC cameras)? If not, why does Apple's documentation claim that iOS 17 supports external devices instead of specifying iPadOS 17 only?
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370
Mar ’25
iPhone 13promax camera issue
Ever since the last update i have issues with my camera app. Sometimes when I open the app the forward facing cameras don’t work and it’s just a Black screen. I also get a warning that I may not have genuine iPhone parts installed. I have to reboot the phone every time just to have it app function again. It’s annoying. Please fix this. I never had any issues with the camera or its app up until after the update.
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161
Mar ’25
Prevent iOS from Switching Between Back Camera Lenses in getUserMedia (Safari/WebView, iOS 18)
I’m developing a hybrid app (WebView / Turbo Native) that uses getUserMedia to access the back camera for a PPG/heart rate measurement feature (the user places their finger on the camera). Problem: Even when I specify constraints like: { video: { deviceId: '...', facingMode: { exact: 'environment' }, advanced: [{ zoom: 1.0 }] }, audio: false } On iPhone 15 (iOS 18), iOS unexpectedly switches between the wide, ultra-wide, and telephoto lenses during the measurement. This breaks the heart rate detection, and it forces the user to move their finger in the middle of the measurement. Question: Is there any way, via getUserMedia/WebRTC, to force iOS to use only the wide-angle lens and prevent automatic lens switching? I know that with AVFoundation (Swift) you can pick .builtInWideAngleCamera, but I’m hoping to avoid building a custom native layer and would prefer to stick with WebView/JavaScript if possible to save time and complexity. Any suggestions, workarounds, or updates from Apple would be greatly appreciated! Thanks a lot!
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Mar ’25
Crash observed in iOS 18.4 beta on opening camera from WebView.
Adding Stack Trace for your reference: thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BREAKPOINT (code=1, subcode=0x1a6efe5b8) frame #0: 0x00000001a6efe5b8 WebCoreWebCore::BaseAudioSharedUnit::BaseAudioSharedUnit() + 668 frame #1: 0x00000001a6efe044 WebCoreWebCore::CoreAudioSharedUnit::singleton() + 80 frame #2: 0x00000001a9521fe4 WebCoreWebCore::CoreAudioCaptureSource::create(WebCore::CaptureDevice const&, WebCore::MediaDeviceHashSalts&&, WebCore::MediaConstraints const*, std::__1::optional<WTF::ObjectIdentifierGeneric<WebCore::PageIdentifierType, WTF::ObjectIdentifierMainThreadAccessTraits<unsigned long long>, unsigned long long>>) + 360 frame #3: 0x00000001a94f180c WebCoreWebCore::RealtimeMediaSourceCenter::getUserMediaDevices(WebCore::MediaStreamRequest const&, WebCore::MediaDeviceHashSalts&&, WTF::Vector<WebCore::RealtimeMediaSourceCenter::DeviceInfo, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc>&, WTF::Vector<WebCore::RealtimeMediaSourceCenter::DeviceInfo, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc>&, WebCore::MediaConstraintType&) + 356 frame #4: 0x00000001a94f22cc WebCoreWebCore::RealtimeMediaSourceCenter::validateRequestConstraintsAfterEnumeration(WTF::Function<void (WTF::Vector<WebCore::CaptureDevice, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc>&&, WTF::Vector<WebCore::CaptureDevice, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc>&&)>&&, WTF::Function<void (WebCore::MediaConstraintType)>&&, WebCore::MediaStreamRequest const&, WebCore::MediaDeviceHashSalts&&) + 356 frame #5: 0x00000001a94fb394 WebCoreWTF::Detail::CallableWrapper<WebCore::RealtimeMediaSourceCenter::enumerateDevices(bool, bool, bool, bool, WTF::CompletionHandler<void ()>&&)::$_0, void>::~CallableWrapper() + 164 frame #6: 0x00000001a814bbe8 WebCoreWTF::Detail::CallableWrapper<WebCore::AVCaptureDeviceManager::refreshCaptureDevicesInternal(WTF::CompletionHandler<void ()>&&, WebCore::AVCaptureDeviceManager::ShouldSetUserPreferredCamera)::$_0::operator()()::'lambda'(), void>::call() + 520 frame #7: 0x00000001ab7f1aac JavaScriptCoreWTF::RunLoop::performWork() + 524 frame #8: 0x00000001ab7f1880 JavaScriptCoreWTF::RunLoop::performWork(void*) + 36 frame #9: 0x00000001935e7d0c CoreFoundationCFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION + 28 frame #10: 0x00000001935e7ca0 CoreFoundation__CFRunLoopDoSource0 + 172 frame #11: 0x00000001935e6a24 CoreFoundation__CFRunLoopDoSources0 + 232 frame #12: 0x00000001935e5c64 CoreFoundation__CFRunLoopRun + 840 frame #13: 0x000000019360a730 CoreFoundationCFRunLoopRunSpecific + 572 frame #14: 0x00000001e0fb5190 GraphicsServicesGSEventRunModal + 168 frame #15: 0x0000000196239f34 UIKitCore-[UIApplication _run] + 816 frame #16: 0x0000000196238164 UIKitCore`UIApplicationMain + 336 frame #17: 0x000000010811bec4 AppName.debug.dylibmain at AppDelegate.swift:25:13 frame #18: 0x00000001bae06a58 dyldstart + 5964
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1.1k
Mar ’25
iPhone 16 Camera Control and AVCaptureSlider – Is there a way to detect which slider is active?
I am following the Apple sample code and trying to add a manual focus lens position slider: @available(iOS 18.0, *) private func addCameraControls() { if !self.session.controls.isEmpty { for control in self.session.controls { self.session.removeControl(control) } } self.cameraControlFocusSlider = nil //Focus Slider if self.videoDevice!.isLockingFocusWithCustomLensPositionSupported { self.cameraControlFocusSlider = AVCaptureSlider("Focus", symbolName: "dot.square", in: 0.0...1.0) self.cameraControlFocusSlider!.setActionQueue(self.sessionQueue) { focusValue in //Do manual focus } if self.session.canAddControl(self.cameraControlFocusSlider!) { self.session.addControl(self.cameraControlFocusSlider!) } } } So there are these AVCaptureSessionControlsDelegate methods: final func sessionControlsDidBecomeActive(_ session: AVCaptureSession) { print ("sessionControlsDidBecomeActive") } final func sessionControlsWillEnterFullscreenAppearance(_ session: AVCaptureSession) { print ("sessionControlsWillEnterFullscreenAppearance") } final func sessionControlsWillExitFullscreenAppearance(_ session: AVCaptureSession) { print ("sessionControlsWillExitFullscreenAppearance") } final func sessionControlsDidBecomeInactive(_ session: AVCaptureSession) { print ("sessionControlsDidBecomeInactive") } So when self.cameraControlFocusSlider is presented, I have to show the current value of the lense position. Lens position can change from auto focus and also from manual focus by the user using the app UI. Is there a way to see if self.cameraControlFocusSlider is active or being used? Please note that I will have more than one AVCaptureSlider in the final code.
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386
Mar ’25
Set the capture device color space to apple log not works.
I set the device format and colorspace to Apple Log and turn off the HDR, why the movie output is still in HDR format rather than ProRes Log? Full runnable demo here: https://github.com/SpaceGrey/ColorSpaceDemo session.sessionPreset = .inputPriority // get the back camera let deviceDiscoverySession = AVCaptureDevice.DiscoverySession(deviceTypes: [.builtInWideAngleCamera], mediaType: .video, position: .back) backCamera = deviceDiscoverySession.devices.first! try! backCamera.lockForConfiguration() backCamera.automaticallyAdjustsVideoHDREnabled = false backCamera.isVideoHDREnabled = false let formats = backCamera.formats let appleLogFormat = formats.first { format in format.supportedColorSpaces.contains(.appleLog) } print(appleLogFormat!.supportedColorSpaces.contains(.appleLog)) backCamera.activeFormat = appleLogFormat! backCamera.activeColorSpace = .appleLog print("colorspace is Apple Log \(backCamera.activeColorSpace == .appleLog)") backCamera.unlockForConfiguration() do { let input = try AVCaptureDeviceInput(device: backCamera) session.addInput(input) } catch { print(error.localizedDescription) } // add output output = AVCaptureMovieFileOutput() session.addOutput(output) let connection = output.connection(with: .video)! print( output.outputSettings(for: connection) ) /* ["AVVideoWidthKey": 1920, "AVVideoHeightKey": 1080, "AVVideoCodecKey": apch,<----- prores has enabled. "AVVideoCompressionPropertiesKey": { AverageBitRate = 220029696; ExpectedFrameRate = 30; PrepareEncodedSampleBuffersForPaddedWrites = 1; PrioritizeEncodingSpeedOverQuality = 0; RealTime = 1; }] */ previewSource = DefaultPreviewSource(session: session) queue.async { self.session.startRunning() } }
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386
Mar ’25
Accessing AV External Storage
Is it possible to use the AVExternalStorageDevice to access external storage from a connected camera or usb drive (via USB C or Lightning connector) on an iPad/iPhone. I have tested the following code on an iPhone 14 (iOS 18.1.1) and an iPad Gen 10 (18.3.1), and both return false for: // returns false on iPhone 14, iPad gen 10 print(AVExternalStorageDeviceDiscoverySession.isSupported) The following code returns null, when I try to access the external storage discovery session. // returns null on iOS devices print(AVExternalStorageDeviceDiscoverySession.shared) The following returns false, without displaying a permission dialog: AVExternalStorageDevice.requestAccess(completionHandler: { (granted: Bool) in // returns false with no permission dialog print(granted); What type of iOS devices are supported by AVExternalStorageDeviceDiscoverySession? What situations has it been used for (e.g. connecting to Camera via the external storage protocol, accessing photos from a SD card with an adapter, accessing photos from usb drive). Is there are sample code for using the AV External Storage api?
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370
Feb ’25
Distortion corrected images
Hi, Currently I am developing a 3D reconstruction project. Which requires images to be distortion-free (rectilinear) and with known intrinsics. The session I am developing on is a builtInDualWideCamera, with isGeometricDistortionCorrectionEnabled set to false to be able to get the intrinsic matrix of the images, isVirtualDeviceConstituentPhotoDeliveryEnabled set to true and isAutoVirtualDeviceFusionEnabled set to false to get both images and isCameraCalibrationDataDeliveryEnabled set to true to actually get the calibration data. The distortion correction parameters such as lensDistortionLookupTable are used. The 42 coefficients mapping array is used as described in the AVCameraCalibrationData header file. A simple piecewise linear interpolation. There are two questions I would like to get support on: A way to set the calibration parameters in each image. I have an approach that sets the parameters in the kCGImagePropertyExifDictionary -> "UserComment". Is there a better approach to write calibration parameter data into the images? I feel like this is a bit dirty and there might be a better and neat approach. For the ultra-wide angle camera's images, the lensDistortionLookupTable contains several zeros at the end of the array. For example (last 10 elements are zero): "LensDistortionLookupTable":"0.000000000000000,0.000349554029526,0.001385628827848,0.003071037586778,... ,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000,0.000000000000000" The problem comes when the complete array is used to correct the image (including zeros), the end result is a wrapped-like-circle image close to the edges of it which is completely wrong. In contrast, if the LensDistortionLookupTable is used without the last zeros and the new size accommodated the image looks better (although not as rectilinear as if you take the image from the iPhone's camera app), but definitely less distorted. Including zeros (full array): Excluding zeros (array size changed): Am I missing an important point in the usage of the lensDistortionLookupTable where this case is addressed (zeros at the end)? What is the criteria to shrink/exclude elements of the array? Any advice is very much welcome.
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393
Feb ’25
Info.plist
Hello, im trying to get my app to be able to ask the device for permission to have access to the camera. To do so i created an info.plist and turned off the generate Info.plist file in packaging. I then added what i believe are all the necessary keys. However, when i try to build and test on my phone i keep running an error that says that my app has a missing or invalid CFBundleExecutable in its info.plist. I tried to fix it by adding Key: CFBundleExecutable Type: String Value: $(EXECUTABLE_NAME) However, this isnt working. I have already added a BundleIdentifier using my com.name.appname the Bundle version string and Bundle Version. Now im not fully sure what to put to fix this issue. Is there another way to get the camera to work without having to create an info.plist? Or is this the only way?
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Feb ’25
Question about how to access to camera on Swift Playground
When I was working on my project for Swift Student Challenge, I found an interesting fact regarding camera access. If I create an App project on Xcode, the camera capture works well on it. However, if I copied and pasted the code on an App Playground project on Xcode, it crashed and output several errors. I am wondering why this is happening.
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442
Feb ’25
input type="file"でアップロードした画像のGPS情報
input type="file"でアップロードした画像データからGPS情報が除去されます。 こちらはiPadOS16.5.1で発生しておりました。 iPadOS17.4.1、iPadOS18.3では正常にGPS情報が保持されます。 iOS、iPadOSのアップデートでGPS情報を保持するよう修正されたと見受けられますが、リリースノートを参照しても上記修正についての記事を見つけられませんでした。 お手数ですが、上記修正に該当する記事をご教示頂けませんでしょうか。 どうぞよろしくお願い致します。
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363
Feb ’25
Macro-mode in AVCaptureDevice(custom camera)
Hi, I would like to use macro-mode for the custom camera using AVCaptureDevice in my project. This feature might help to automatically adjust and switch between lenses to get a close up clear image. It looks like this feature is not available and there are no open apis to achieve macro mode from Apple. Is there a way to get this functionality in the custom camera without losing the image quality. Please let me know if this is possible. Thanks you, Adil Thamarasseri
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1.2k
Feb ’25
Torch Freezes Ultra-Wide Camera When Switching Between Wide & Ultra-Wide Lenses (AVFoundation Bug?)
I'm developing an iOS app using AVFoundation for real-time video capture and object detection. While implementing torch functionality with camera switching (between Wide and Ultra-Wide lenses), I encountered a critical issue where the camera freezes when toggling the torch while the Ultra-Wide camera is active. Issue If the torch is ON and I switch from Wide to Ultra-Wide, the camera freezes If the Ultra-Wide camera is active and I try to turn the torch ON, the camera freezes The iPhone Camera app allows using the torch while recording video with the Ultra-Wide lens, so this should be possible via AVFoundation as well. Code snippet DispatchQueue.global(qos: .userInitiated).async { [weak self] in guard let self = self else { return } let isSwitchingToUltraWide = !self.isUsingFisheyeCamera let cameraType: AVCaptureDevice.DeviceType = isSwitchingToUltraWide ? .builtInUltraWideCamera : .builtInWideAngleCamera let cameraName = isSwitchingToUltraWide ? "Ultra Wide" : "Wide" guard let selectedCamera = AVCaptureDevice.default(cameraType, for: .video, position: .back) else { DispatchQueue.main.async { self.showAlert(title: "Camera Error", message: "\(cameraName) camera is not available on this device.") } return } do { let currentInput = self.videoCapture.captureSession.inputs.first as? AVCaptureDeviceInput self.videoCapture.captureSession.beginConfiguration() if isSwitchingToUltraWide &amp;&amp; self.isFlashlightOn { self.forceEnableTorchThroughWide() } if let currentInput = currentInput { self.videoCapture.captureSession.removeInput(currentInput) } let videoInput = try AVCaptureDeviceInput(device: selectedCamera) self.videoCapture.captureSession.addInput(videoInput) self.videoCapture.captureSession.commitConfiguration() self.videoCapture.updateVideoOrientation() DispatchQueue.main.async { if let barButton = sender as? UIBarButtonItem { barButton.title = isSwitchingToUltraWide ? "Wide" : "Ultra Wide" barButton.tintColor = isSwitchingToUltraWide ? UIColor.systemGreen : UIColor.white } print("Switched to \(cameraName) camera.") } self.isUsingFisheyeCamera.toggle() } catch { DispatchQueue.main.async { self.showAlert(title: "Camera Error", message: "Failed to switch to \(cameraName) camera: \(error.localizedDescription)") } } } } Expected Behavior Torch should be able to work when Ultra-Wide is active, just like the iPhone Camera app does. The camera should not freeze when switching between Wide and Ultra-Wide with the torch ON. AVCaptureSession should not crash when toggling the torch while Ultra-Wide is active. Questions &amp; Help Needed Is this a known issue with AVFoundation? How does the iPhone Camera app allow using the torch while recording in Ultra-Wide? What’s the correct way to switch between Wide and Ultra-Wide cameras without freezing when the torch is active? Info Device tested: iPhone 13 Pro / iPhone 15 Pro / Iphone 15 iOS Version: iOS 17.3 / iOS 18.0 Xcode Version: 16.2
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446
Feb ’25
Camera USB
am new to using Swift for a Mac Application. I am trying to control an external UVC-compliant camera focus and other capabilities. However, I'm having trouble with this and don't know where to start. I have downloaded an application from the App Store and it can control the focus and other capabilities. I've tried IOKit but this seems to be complicated and this does not return any capabilities or control the camera. I also tried AVfoundation and was able to open the camera, but using the following code did not work for me. as a device.isFocusPointOfInterestSupported returns false and without checking the app crashes. @IBAction func focusChanged(_ sender: NSSlider) { do { guard let device = videoDevice else { return } try device.lockForConfiguration() // Check if focus mode and point of interest are supported if device.isFocusModeSupported(.locked) { device.focusMode = .locked } if device.isFocusPointOfInterestSupported { // Map the slider value (0.0 to 1.0) to the focus point's X coordinate let focusX = CGFloat(sender.doubleValue) let focusPoint = CGPoint(x: focusX, y: 0.5) // Y coordinate is typically 0.5 (centered vertically) device.focusPointOfInterest = focusPoint } else { print("Focus point of interest is not supported on this device.") } device.unlockForConfiguration() // Log focus settings print("Focus point: \(device.focusPointOfInterest)") print("Focus mode: \(device.focusMode.rawValue)") } catch { print("Error adjusting focus: \(error)") } Any help or advice is much appreciated.
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443
Jan ’25
Use Metal to conver HDR Pixelbuffer to SDR Pixelbuffer
I see some demo show convert HDR video to SDR Pixelbuffer,such AVAssetReader、 AVVideoComposition 、AVComposition 、AVFoundation. But In some cases,I want to render HDR Pixelbuffer and record video. AVCaptureSession *session = [[AVCaptureSession alloc] init]; session.sessionPreset = AVCaptureSessionPresetHigh; AVCaptureDevice *videoDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo]; if ([videoDevice isVideoHDRSupported]) { NSError *error = nil; if ([videoDevice lockForConfiguration:&error]) { videoDevice.automaticallyAdjustsVideoHDREnabled = NO; videoDevice.videoHDREnabled = YES; // 开启 HDR [videoDevice unlockForConfiguration]; } else { NSLog(@"Error: %@", error.localizedDescription); } } Real-time processing of HDR data requires processing of video frame data (such as filters), ensuring that the processing chain supports 10-bit color depth and HDR metadata. And use imagesBuffer to object tracking, etc. How to solve this problem?
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429
Jan ’25
How to share 'back facing' iOS camera app at same time Eye Tracking app needs 'front facing' camera?
While using my xmas present of a new iPhone and iOS 18.2, I figured I'd try the Eye Tracker app. I've been working with clients successfully using Tobii and other existing eye trackers. In my limited tests, Apple has room for improvement. My main issue is with the camera app which cannot be used at the same time while using the Eye Tracker app. I get an error popup from Apple: Camera is use by another app The image below is from my app showing the popup message "Camera in use by another app", but the same error occurs on the installed camera app. This error is from Apple, not my app. For terminology: 'front' camera is the one pointing at the user (the selfi camera) while 'back' camera is the main one with multiple lenses. Eye tracking needs the 'front' camera. It seems when an app uses the camera, it takes over both the front and back facing cameras (since you might swap them). Thus another app, especially Eye Tracking, cannot use just the front facing camera at the same time. That limits use of Eye Tracking, in particular one cannot take pictures or click any buttons on an app that uses the camera. Anyone know of a way for an app to not take over both front and back cameras at the same time? If I can separate them, the Eye Tracker could use the front camera while the camera uses the back camera.
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372
Jan ’25
Combining ARKit Face Tracking with High-Resolution AVCapture and Perspective Rendering on Front Camera
Subject: Combining ARKit Face Tracking with High-Resolution AVCapture and Perspective Rendering on Front Camera Message: Hello Apple Developer Community, We’re developing an application using the front camera that requires both real-time ARKit face tracking/guidance and the capture of high-resolution still images via AVCaptureSession. Our goal is to leverage ARKit’s depth and face data to render a captured image from another perspective post-capture, maintaining high image quality. Our Approach: Real-Time ARKit Guidance: Utilize ARKit (e.g., ARFaceTrackingConfiguration) for continuous face tracking, depth, and scene understanding to guide the user in real time. High-Resolution Capture Transition: At the moment of capture, we plan to pause the ARKit session and switch to an AVCaptureSession to take a high-resolution image. We assume that for a front-facing image, the subject’s face is directly front-on, and the relative pose between the face and camera remains the same during the transition. The only variation we expect is a change in distance. Our intention is to minimize the delay between the last ARKit frame and the high-res capture to maintain temporal consistency, assuming that aside from distance, the face-camera relative pose remains unchanged. Post-Processing Perspective Rendering: Using the last ARKit face data (depth, pose, and landmarks) along with the high-resolution 2D image, we aim to render the scene from another perspective. We want to correct the perspective of the 2D image using SceneKit or RealityKit, leveraging the collected ARKit scene information to achieve a natural, high-quality rendering from a different viewpoint. The rendering should match the quality of a normally captured high-resolution image, adjusting for the difference in distance while using the stored ARKit data to correct perspective. Our Questions: Session Transition Best Practices: What are the recommended best practices to seamlessly pause ARKit and switch to a high-resolution AVCapture session on the front camera How can we minimize user movement or other issues during this brief transition, given our assumption that the face-camera pose remains largely consistent except for distance changes? Data Integration for Perspective Rendering: How can we effectively integrate stored ARKit face, depth, and pose data with the high-res image to perform accurate perspective correction or rendering from another viewpoint? Given that we assume the relative pose is constant except for distance, are there strategies or APIs to leverage this assumption for simplifying the perspective transformation? Perspective Correction with SceneKit/RealityKit: What techniques or workflows using SceneKit or RealityKit are recommended for correcting the perspective of a captured 2D image based on ARKit scene data? How can we use these frameworks to render the high-resolution image from an alternative perspective, while maintaining image quality and fidelity? 4. Pitfalls and Guidelines: What common pitfalls should we be aware of when combining ARKit tracking data with high-res capture and post-processing for perspective rendering? Are there performance considerations, recommended thresholds for acceptable temporal consistency, or validation techniques to ensure the ARKit data remains applicable at the moment of high-res capture? We appreciate any advice, sample code references, or documentation pointers that could assist us in implementing this workflow effectively. Thank you!
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709
Jan ’25