Hello, I am getting the following errors when building a Mac Camera Extension with web sockets. I am using URLSessionWebsocketTask as my web socket library. I built a test program for my code and in there I can see my web sockets are working properly, but when I run it from the System Extension I get the following errors. The socket opens for two - three messages then crashes. I couldnt find any documentation online for the following errors CMIOExtensionProvider.m:1975:-[CMIOExtensionProvider removeProviderContext:]_block_invoke Unregistered provider context <CMIOExtensionProviderContext: ->, don't be surprised if things go badly CMIOExtensionProviderContext.m:64:-[CMIOExtensionProviderContext initWithConnection:]_block_invoke [391] received Connection invalid``

Hello Apple Developer Support, I’m developing a virtual camera using the CMIOExtensionDevice / CMIOExtensionStreamSource APIs on macOS. While the virtual camera appears in system settings and apps like Zoom and Google Meet, the video output exhibits the following issues: Jittering frames: The first frame sometimes appears correctly, but subsequent frames flicker or jitter. Solid color fill: Eventually, the camera feed fills entirely with a solid accent color (e.g., blue), rather than the intended video content. Console logs: Repeated messages appear in Console.app: Invalid display 0x00000000 Setup details: The virtual camera is created using CMIOExtensionDevice and CMIOExtensionStream. Video frames are rendered from NSImage/CGImage using CGContext and copied into CVPixelBuffers. Frame delivery is controlled by a DispatchSourceTimer at 60 FPS. macOS version: 26.2 Xcode version: 26.1 Observations: The Invalid display 0x00000000 logs suggest that CGContext drawing or NSImage operations are failing in headless mode (i.e., there is no real display attached to the virtual camera). Using CIContext with .useSoftwareRenderer = true appears to mitigate some flicker, but not entirely. Questions / Requests: Is it expected that CoreMediaIO virtual cameras cannot reliably render CGImage / NSImage frames offscreen? Are there recommended APIs or approaches to render virtual camera frames fully headless to avoid display-dependent jitter? Is there any documentation or sample code from Apple showing stable video output from a virtual camera extension that does not rely on a physical display? Any guidance or examples would be greatly appreciated. This issue prevents the virtual camera from being used reliably in standard video apps. Thank you, Savvy

Hello Apple Developer Support, I’m developing a virtual camera using the CMIOExtensionDevice / CMIOExtensionStreamSource APIs on macOS. While the virtual camera appears in system settings and apps like Zoom and Google Meet, the video output exhibits the following issues: Jittering frames: The first frame sometimes appears correctly, but subsequent frames flicker or jitter. Solid color fill: Eventually, the camera feed fills entirely with a solid accent color (e.g., blue), rather than the intended video content. Console logs: Repeated messages appear in Console.app: Invalid display 0x00000000 Setup details: The virtual camera is created using CMIOExtensionDevice and CMIOExtensionStream. Video frames are rendered from NSImage/CGImage using CGContext and copied into CVPixelBuffers. Frame delivery is controlled by a DispatchSourceTimer at 60 FPS. macOS version: [Your macOS version here] Xcode version: [Your Xcode version here] Observations: The Invalid display 0x00000000 logs suggest that CGContext drawing or NSImage operations are failing in headless mode (i.e., there is no real display attached to the virtual camera). Using CIContext with .useSoftwareRenderer = true appears to mitigate some flicker, but not entirely. Questions / Requests: Is it expected that CoreMediaIO virtual cameras cannot reliably render CGImage / NSImage frames offscreen? Are there recommended APIs or approaches to render virtual camera frames fully headless to avoid display-dependent jitter? Is there any documentation or sample code from Apple showing stable video output from a virtual camera extension that does not rely on a physical display? Any guidance or examples would be greatly appreciated. This issue prevents the virtual camera from being used reliably in standard video apps. Thank you, Savvy

Hello, I am developing a custom player SDK based on AVPlayer. While testing LL-HLS streams, I intermittently encounter the following error: Error Domain=CoreMediaErrorDomain Code=-12880 Since I cannot find documentation for this specific code, could you please clarify its meaning? Specifically, I would like to know if this is a critical error that disrupts playback, or if it is just a warning that can be safely ignored. Any insights would be appreciated. Thank you.

I made a CMIOExtension (a virtual camera) which generates its own output, for use in our in-house software testing. I wanted to make a video source with 29.97, 30, 59.94 and 60fps output. To this end, I created a CMIOExtensionDeviceSource which creates a CMIOExtensionDevice with one CMIOExtensionStreamSource with various stream formats contained in [CMIOExtensionStreamFormat], including one with both maxFrameDuration and minFrameDuration = CMTimeMake(value: 1000, timescale: 30000) and another with both maxFrameDuration and minFrameDuration = CMTimeMake(value: 1001, timescale: 30000) I've held off on the creation of the 59.94/60fps source for now until this problem is resolved. my virtual camera works, it produces a signal, but when I examine its associated AVCaptureDevice in the debugger, I find (lldb) po self.captureDevice?.formats[0].videoSupportedFrameRateRanges[0].maxFrameDuration ▿ Optional<CMTime> ▿ some : CMTime - value : 1000000 - timescale : 30000000 ▿ flags : CMTimeFlags - rawValue : 1 - epoch : 0 I get the same value, 1000000/30000000, or exactly 30fps, for all the formats of my AVCaptureDevice. Is there something I'm doing wrong, or do CMIOExtensionDevices always round the frame rates? I can't force CoreMediaIO to produce frames at exactly my desired frame interval, but I'd like to ensure that the average frame rate is my desired rate. How can I do that? Frame emission is governed by a repeating DispatchSourceTimer with a repeat time specified in nanoseconds with the TimerFlags set to 'strict'.

Hello, I am currently developing a video player using Custom AVPlayer SDK and testing LL-HLS live streaming. I encountered a specific error, CoreMediaErrorDomain -15418, during playback. I have searched through the official documentation and the forums, but I could not find any information regarding this error code. I would like to inquire about the following: Description & Cause: What does the error code -15418 specifically represent in the context of CoreMedia and LL-HLS? Severity: Is this a critical error that halts playback, or is it merely a warning? Environment Details: iOS Version: iOS 26.2 Device: iPhone 15 Pro Max Stream Type: LL-HLS (Low-Latency HLS) Impact: Quality drops Any insights or references to documentation would be greatly appreciated. Thank you.

Hi I have a monitoring app, that will take input video from uvc and process it using Metal, and eventually get a MTLTexture. The problem I'm facing is I have to convert MTLTexture to CGImage then call TextureResource.replace, which is super slow. Metal processing speed is same as input frame rate(50pfs), but MTLTexture -> CGImage -> TextureResource only got 7fps... Is there any way I can make it faster?

Hi, I'm working an a video editing software that lets you composite and export videos. I use a custom compositor to apply my effects etc. In my crash dashboard, I am seeing a report of an EXC_BAD_ACCESS crash from objc_msgSend. Below is the stacktrace. libobjc.A.dylib objc_msgSend libdispatch.dylib _dispatch_sync_invoke_and_complete_recurse libdispatch.dylib _dispatch_sync_f_slow [symbolication failed] libdispatch.dylib _dispatch_client_callout libdispatch.dylib _dispatch_lane_barrier_sync_invoke_and_complete AVFCore -[AVCustomVideoCompositorSession(AVCustomVideoCompositorSession_FigCallbackHandling) _customCompositorShouldCancelPendingFrames] AVFCore _customCompositorShouldCancelPendingFramesCallback MediaToolbox remoteVideoCompositor_HandleVideoCompositorClientMessage CoreMedia __figXPCConnection_CallClientMessageHandlers_block_invoke libdispatch.dylib _dispatch_call_block_and_release libdispatch.dylib _dispatch_client_callout libdispatch.dylib _dispatch_lane_serial_drain libdispatch.dylib _dispatch_lane_invoke libdispatch.dylib _dispatch_root_queue_drain_deferred_wlh libdispatch.dylib _dispatch_workloop_worker_thread libsystem_pthread.dylib _pthread_wqthread libsystem_pthread.dylib start_wqthread What stood out to me is that this is only being reported from IOS 26.0+ devices. A part of the stacktrace failed to be symbolicated [symbolication failed]. I'm 90% confident that this is Apple code, not my app's code. I cannot reproduce this locally. Is this a known issue? What are the possible root-causes, and how can I verify/eliminate them? Thanks,

I'm capturing video stream from GoPro camera (via UDP MPEG-TS packets) but unable to play in iOS app. can someone provide a source code to decode MPEG-TS data to CMSampleBuffer.

I developed a driverkit extension based on overriding-the-default-usb-video-class-extension, but the link didn’t give the details of realization. I asked DTS who gave two tips: 1, Do you also have a CMIO extension to load in place of the default overriding-the-default-usb-video-class-extension 2, Your DriverKit extension’s info.plist is also missing the CameraAssistantBundleID. I want to know why a driverkit extension needs a CMIO extension, what’s the data and control flow?

Does anyone have a template of an Apple Projected Media Profile Format Description or a File of a Stereo wideFOV video? Use case I have 2 compatible cameras that I stereo sync and I want to move the projection information from the compatible video to the Spatial video that combines them. Every version I can come up with crashes the AVP and when viewing as Spatial in Tahoe I just get a black screen.

Hello, I need to enumerate built-in media devices (cameras, microphones, etc.). For this purpose, I am using the CoreAudio and CoreMediaIO frameworks. According to the table 'Daemon-Safe Frameworks' in Apple’s TN2083, CoreAudio is daemon-safe. However, the documentation does not mention CoreMediaIO. Can CoreMediaIO be used in a daemon? If not, are there any documented alternatives to detect built-in cameras in a daemon (e.g., via device classes in IOKit)? Thank you in advance, Pavel

I am doing something similar to this post Within an AVCaptureDataOutputSynchronizerDelegate method, I create a pixelBuffer using CVPixelBufferCreate with the following attributes: kCVPixelBufferIOSurfacePropertiesKey as String: true, kCVPixelBufferIOSurfaceOpenGLESTextureCompatibilityKey as String: true When I copy the data from the vImagePixelBuffer "rotatedImageBuffer", I get the following error: Thread 10: EXC_BAD_ACCESS (code=1, address=0x14caa8000) I get the same error with memcpy and data.copyBytes (not running them at the same time obviously). If I use CVPixelBufferCreateWithBytes, I do not get this error. However, CVPixelBufferCreateWithBytes does not let you include attributes (see linked post above). I am using vImage because I need the original CVPixelBuffer from the camera output and a rotated version with a different color scheme. // Copy to pixel buffer let attributes: NSDictionary = [ true : kCVPixelBufferIOSurfacePropertiesKey, true : kCVPixelBufferIOSurfaceOpenGLESTextureCompatibilityKey, ] var colorBuffer: CVPixelBuffer? let status = CVPixelBufferCreate(kCFAllocatorDefault, Int(rotatedImageBuffer.width), Int(rotatedImageBuffer.height), kCVPixelFormatType_32BGRA, attributes, &colorBuffer) //let status = CVPixelBufferCreateWithBytes(kCFAllocatorDefault, Int(rotatedImageBuffer.width), Int(rotatedImageBuffer.height), kCVPixelFormatType_32BGRA, rotatedImageBuffer.data, rotatedImageBuffer.rowBytes, nil, nil, attributes as CFDictionary, &colorBuffer) // does NOT produce error, but also does not have attributes guard status == kCVReturnSuccess, let colorBuffer = colorBuffer else { print("Failed to create buffer") return } let lockFlags = CVPixelBufferLockFlags(rawValue: 0) guard kCVReturnSuccess == CVPixelBufferLockBaseAddress(colorBuffer, lockFlags) else { print("Failed to lock base address") return } let colorBufferMemory = CVPixelBufferGetBaseAddress(colorBuffer)! let data = Data(bytes: rotatedImageBuffer.data, count: rotatedImageBuffer.rowBytes * Int(rotatedImageBuffer.height)) data.copyBytes(to: colorBufferMemory.assumingMemoryBound(to: UInt8.self), count: data.count) // Fails here //memcpy(colorBufferMemory, rotatedImageBuffer.data, rotatedImageBuffer.rowBytes * Int(rotatedImageBuffer.height)) // Also produces the same error CVPixelBufferUnlockBaseAddress(colorBuffer, lockFlags)

My current app implements a custom video player, based on a AVSampleBufferRenderSynchronizer synchronising two renderers: an AVSampleBufferDisplayLayer receiving decoded CVPixelBuffer-based video CMSampleBuffers, and an AVSampleBufferAudioRenderer receiving decoded lpcm-based audio CMSampleBuffers. The AVSampleBufferRenderSynchronizer is started when the first image (in presentation order) is decoded and enqueued, using avSynchronizer.setRate(_ rate: Float, time: CMTime), with rate = 1 and time the presentation timestamp of the first decoded image. Presentation timestamps of video and audio sample buffers are consistent, and on most streams, the audio and video are correctly synchronized. However on some network streams, on iOS, the audio and video aren't synchronized, with a time difference that seems to increase with time. On the other hand, with the same player code and network streams on macOS, the synchronization always works fine. This reminds me of something I've read, about cases where an AVSampleBufferRenderSynchronizer could not synchronize audio and video, causing them to run with independent and potentially drifting clocks, but I cannot find it again. So, any help / hints on this sync problem will be greatly appreciated! :)

Hello Apple Developer Community, I am trying to play an HLS stream using the React Native Video player (underneath it's using AvPlayer). I am able to play the stream smoothly, but in some cases the player can not play the stream properly. Behaviour: react-native-video: I am getting the below error. Error details from react-native-video player: Error Code: -12971 Domain: CoreMediaErrorDomain Localised Description: The operation couldn’t be completed. (CoreMediaErrorDomain error -12971.) Target: 2457 The error does not provide a specific failure reason or recovery suggestion, which makes troubleshooting challenging. AvPlayer on native iOS project: Video playback stopped after playing a few seconds. AVPlayer configuration: player.currentItem?.preferredForwardBufferDuration = 1 player.automaticallyWaitsToMinimizeStalling = true N.B.: The same buffer duration is working perfectly for others. Stream properties: video resolution: 1280 x 720 I have attached an overview report generated from MediaStreamValidator. I would appreciate any insights or suggestions on how to address this error. Has anyone in the community experienced a similar issue or have any advice on potential solutions? Thank you for your help!