context:Explore low-latency video encoding with VideoToolbox https://developer.apple.com/videos/play/wwdc2021/10158/ I see above post said HEVC VideoToolbox can support SVC, temporal layering of streams in low-latency mode with all P frames. my question is that Does HEVC VideoToolbox support temporal layering of streams with B-frames ?? thanks

Does videotoolbox hevc encoder on iphone16 pro encode with 10bit hdr vui info in bitstream ? I want to encode 4k 10bit hdr bitstream with vui info use hevc videotoolbox .but I don't know how to encode vui info in bitstream ? please give me some sample code ?

Is there sample code on how to use VTFrameProcessorOpticalFlow?

it seems that video toolbox in ios26 is having trouble decoding h.264 streams I have filed a bug report under https://feedbackassistant.apple.com/feedback/20741484

方法不执行，当我点击avplayerviewcontroller 全屏点击返回按钮 时 func playerViewController(_ playerViewController: AVPlayerViewController, willEndFullScreenPresentationWithAnimationCoordinator coordinator: UIViewControllerTransitionCoordinator) 没有执行

I'm building a Swift video editor with AVFoundation and a custom compositor. Despite setting AVVideoComposition.frameDuration to 60 FPS, I'm seeing significant frame skipping during playback. Console Output Shows Frame Skipping Frame #0 at 0.0 ms (fps: 60.0) Frame #2 at 33.333333333333336 ms (fps: 60.0) Frame #6 at 100.0 ms (fps: 60.0) Frame #10 at 166.66666666666666 ms (fps: 60.0) Frame #32 at 533.3333333333334 ms (fps: 60.0) Frame #62 at 1033.3333333333335 ms (fps: 60.0) Frame #96 at 1600.0 ms (fps: 60.0) Instead of frames every ~16.67ms (60 FPS), I'm getting irregular intervals, sometimes 33ms, 67ms, or hundreds of milliseconds apart. Renderer.swift (Key Parts) @MainActor class Renderer: ObservableObject { @Published var playerItem: AVPlayerItem? private let assetManager: ProjectAssetManager? private let compositorId: String func buildComposition() async { // ... load mouse moves/clicks data ... let composition = AVMutableComposition() let videoTrack = composition.addMutableTrack( withMediaType: .video, preferredTrackID: kCMPersistentTrackID_Invalid ) var currentTime = CMTime.zero var layerInstructions: [AVMutableVideoCompositionLayerInstruction] = [] // Insert video segments for videoURL in videoURLs { let asset = AVAsset(url: videoURL) let tracks = try await asset.loadTracks(withMediaType: .video) let assetVideoTrack = tracks.first let duration = try await asset.load(.duration) try videoTrack.insertTimeRange( CMTimeRange(start: .zero, duration: duration), of: assetVideoTrack, at: currentTime ) let layerInstruction = AVMutableVideoCompositionLayerInstruction(assetTrack: videoTrack) let transform = try await assetVideoTrack.load(.preferredTransform) layerInstruction.setTransform(transform, at: currentTime) layerInstructions.append(layerInstruction) currentTime = CMTimeAdd(currentTime, duration) } let videoComposition = AVMutableVideoComposition() videoComposition.frameDuration = CMTime(value: 1, timescale: 60) // 60 FPS // Set render size from first video if let firstURL = videoURLs.first { let firstAsset = AVAsset(url: firstURL) let firstTrack = try await firstAsset.loadTracks(withMediaType: .video).first let naturalSize = try await firstTrack.load(.naturalSize) let transform = try await firstTrack.load(.preferredTransform) videoComposition.renderSize = CGSize( width: abs(naturalSize.applying(transform).width), height: abs(naturalSize.applying(transform).height) ) } let instruction = CompositorInstruction() instruction.timeRange = CMTimeRange(start: .zero, duration: currentTime) instruction.layerInstructions = layerInstructions instruction.compositorId = compositorId videoComposition.instructions = [instruction] videoComposition.customVideoCompositorClass = CustomVideoCompositor.self let playerItem = AVPlayerItem(asset: composition) playerItem.videoComposition = videoComposition self.playerItem = playerItem } } class CompositorInstruction: NSObject, AVVideoCompositionInstructionProtocol { var timeRange: CMTimeRange = .zero var enablePostProcessing: Bool = false var containsTweening: Bool = false var requiredSourceTrackIDs: [NSValue]? var passthroughTrackID: CMPersistentTrackID = kCMPersistentTrackID_Invalid var layerInstructions: [AVVideoCompositionLayerInstruction] = [] var compositorId: String = "" } class CustomVideoCompositor: NSObject, AVVideoCompositing { var sourcePixelBufferAttributes: [String : Any]? = [ kCVPixelBufferPixelFormatTypeKey as String: Int(kCVPixelFormatType_32BGRA) ] var requiredPixelBufferAttributesForRenderContext: [String : Any] = [ kCVPixelBufferPixelFormatTypeKey as String: Int(kCVPixelFormatType_32BGRA) ] func renderContextChanged(_ newRenderContext: AVVideoCompositionRenderContext) {} func startRequest(_ asyncVideoCompositionRequest: AVAsynchronousVideoCompositionRequest) { guard let sourceTrackID = asyncVideoCompositionRequest.sourceTrackIDs.first?.int32Value, let sourcePixelBuffer = asyncVideoCompositionRequest.sourceFrame(byTrackID: sourceTrackID), let outputBuffer = asyncVideoCompositionRequest.renderContext.newPixelBuffer() else { asyncVideoCompositionRequest.finish(with: NSError(domain: "VideoCompositor", code: -1)) return } let videoComposition = asyncVideoCompositionRequest.renderContext.videoComposition let frameDuration = videoComposition.frameDuration let fps = Double(frameDuration.timescale) / Double(frameDuration.value) let compositionTime = asyncVideoCompositionRequest.compositionTime let seconds = CMTimeGetSeconds(compositionTime) let frameInMilliseconds = seconds * 1000 let frameNumber = Int(round(seconds * fps)) print("Frame #\(frameNumber) at \(frameInMilliseconds) ms (fps: \(fps))") asyncVideoCompositionRequest.finish(withComposedVideoFrame: outputBuffer) } func cancelAllPendingVideoCompositionRequests() {} } VideoPlayerViewModel @MainActor class VideoPlayerViewModel: ObservableObject { let player = AVPlayer() private let renderer: Renderer func loadVideo() async { await renderer.buildComposition() if let playerItem = renderer.playerItem { player.replaceCurrentItem(with: playerItem) } } } What I've Tried Frame skipping is consistent—exact same timestamps on every playback Issue persists even with minimal processing (just passing through buffers) Occurs regardless of compositor complexity Please note that I need every frame at exact millisecond intervals for my application. Frame loss or inconsistent frameInMillisecond values are not acceptable.

Hey everyone, I'm stuck on a really frustrating AVFoundation problem. I'm building a video editor that uses a custom AVVideoCompositor to add effects, and I need the final output to be 60 FPS. So basically, I create an AVMutableComposition to sequence my video clips. I create an AVMutableVideoComposition and set the frame rate to 60 FPS: videoComposition.frameDuration = CMTime(value: 1, timescale: 60) I assign my CustomVideoCompositor class to the videoComposition. I create an AVPlayerItem with the composition and video composition. The Problem: Playback Works: When I play the AVPlayerItem in an AVPlayer, it's perfect. It plays at a smooth 60 FPS, and my custom compositor's startRequest method is called 60 times per second. Export Fails: When I try to export the exact same composition and video composition using AVAssetExportSession, the final .mp4 file is always 30 FPS (or 29.97). I've logged inside my custom compositor during the export, and it's definitely being called 30 times per second, so it's generating the 30 frames. It seems like AVAssetExportSession is just dropping every other frame when it encodes the video. My source videos are screen recordings which I recorded using ScreenCaptureKit itself with the minimum frame interval to be 60. Here is my export function. I'm using the AVAssetExportPresetHighestQuality preset :- func exportVideo(to outputURL: URL) async throws { guard let composition = composition, let videoComposition = videoComposition else { throw VideoCompositionError.noValidVideos } try? FileManager.default.removeItem(at: outputURL) guard let exportSession = AVAssetExportSession( asset: composition, presetName: AVAssetExportPresetHighestQuality // Is this the problem? ) else { throw VideoCompositionError.trackCreationFailed } exportSession.outputFileType = .mp4 exportSession.videoComposition = videoComposition // This has the 60fps setting try await exportSession.export(to: outputURL, as: .mp4) } I've created a bare bones sample project that shows this exact bug in action. The resulting video is 60fps during playback, but only 30fps during the export. https://github.com/zaidbren/SimpleEditor My Question: Why is AVAssetExportSession ignoring my 60 FPS frameDuration and defaulting to 30 FPS, even though AVPlayer respects it?

Hi everyone, I’m exploring using the iPhone 17 Pro with the Blackmagic ProDock in a custom capture app. The genlock functionality seems accessible via AVExternalSyncDevice and related APIs, which is great. I’m specifically curious about external timecode coming in from the ProDock: • Is there a public way to access the timecode feed in a custom app via AVFoundation or another Apple API? • If so, what is the recommended approach to read or apply that timecode during capture? • Are there any current limitations or entitlements required to access timecode from ProDock in a third-party app? I’m excited to start integrating synchronized capture in my app, and any guidance or sample patterns would be greatly appreciated. Thanks in advance! — [Artem]

How to USE iphone16 pro to capture HDR dolby_vision and use videotoolbox to encode with dolby_vision metadata in bitstream! I know apple ios system can achieve this target,but I want to get source code how to do that ?

I’m implementing FairPlay offline streaming on iOS and ran into a question about DRM expiration handling. As far as I understand, when issuing a FairPlay offline license, there are typically two time windows: 1. The period during which the user can start offline playback (the longer “rental window”). 2. Once playback starts, the duration allowed to complete playback (the shorter “playback window”). I’d like to display this information (the remaining validity or expiration time) in the app’s UI next to each downloaded asset. My question is: 👉 Is there a way to programmatically check or retrieve the expiration time for a FairPlay offline asset on the client side (via AVFoundation or AVContentKeySession)? Any guidance or best practices for surfacing DRM expiration info in the UI would be greatly appreciated.

We're distributing a virtual camera with our app that does not profit in the slightest from automatically applied system video effects both to the video going in (physical camera device) or out (virtual camera device). I'm aware of setting NSCameraReactionEffectGesturesEnabledDefault in Info.plist and determining active video effects via AVCaptureDevice API. Those are obviously crutches, because having to tell users to go look for and click around in menu bar apps is the opposite of a great UX. To make our product's video output more deterministic, I'm looking for a way to tell the CMIO subsystem that our virtual camera does not support any of the system video effects. I'm seeing properties like AVCaptureDevice.Format.isPortraitEffectSupported and AVCaptureDevice.Format.isStudioLightSupported whose documentation refers to the format's ability to support these effects. Since we're setting a CMFormatDescription via CMIOExtensionStreamSource.formats I was hoping to find something in the extensions, but wasn't successful so far. Can this be done?

iPhoneで撮影した映像をブラウザのアプリへ送信して画面に映す機能を持ったアプリを開発しています。 iPhone 17 Pro, 17 Pro Maxでこのアプリを利用するとブラウザ側に表示される映像が緑一色や、緑がメインのカラフルな映像になってしまいます。 調べてみると17Proと17ProMaxで超広角カメラと望遠カメラの画素数が変更になっている（1200万画素→4800万画素）ためエンコーディングで失敗しているのではないかと疑っています。 なんでも情報下さい。 環境情報 WebRTCライブラリ： GoogleWebRTC バージョン 1.1 (CocoaPodsで導入) シグナリングサーバー： AWS Kinesis Video Streams 問題が発生するデバイス： モデル名: iPhone18,1, OS: 26.0 モデル名: iPhone18,1, OS: 26.1 問題が発生しないデバイス： iPhone17,5 以前の多数のモデル モデル名: iPhone18,1, OS: 26.0 モデル名: iPhone18,3, OS: 26.0

I'm using the SwiftUI Photos Picker to select videos from the users Photos library and then opening the video using the PhotosPickerItem. I'm looking for a way to allow the user to open the same video on their other devices as the app uses SwiftData and CloudKit to provide access to a recently watched list of videos. The URL from the PhotosPickerItem appears to be device specific and so I was looking to see if I can use the itemIdentifier and then the init that takes the itemIdentifier to create the PhotosPickerItem on the other devices. The itemIdentifier however is always nil and so wouldn't be able to be used in this way. Is there an alternative approach whereby the users can open a video using a PhotosPickerItem and that item would be viewable on their other devices with an item identifier or a URL that is device agnostic. This approach should also not involve copying the video into other storage as it would simply expand the use of the users iCloud storage, providing a less than ideal user experience. If the user has opened the video from their Photos library, there should be a way to allow the same user (e.g. same Apple ID), to use the same app on another device to open the video again.

When trying to record ProRes RAW (btp2) with AVAssetWriter I get several types of errors: -12780 or -11875. I wonder if recording ProRes RAW can only be done through AVCaptureMovieFileOutput, or if there a way to correctly configure AVAssetWriter to do it.

Adding both AVCaptureMovieFileOutput and AVCaptureVideoDataOutput is supported in AVCaptureSession as seen in documentation (copied snippet below) but then when AVCaptureDevice is configured with ProRes422 codec, it fails unless one of the two outputs is removed from the capture session. It is very much reproducible on iPhone 14 pro running iOS 26.0. Prior to iOS 16, you can add an AVCaptureVideoDataOutput and an AVCaptureMovieFileOutput to the same session, but only one may have its connection active. If you attempt to enable both connections, the system chooses the movie file output as the active connection and disables the video data output’s connection. For apps that link against iOS 16 or later, this restriction no longer exists.

Playback of any kind of HD H.264 MP4 files (720p, 50fps) could randomly cause a stalled image. Playback does not stop in such a case. Image is frozen/stalled. Audio goes on. Timeline goes on. By tapping play/pause or scrubbing in the timeline, the playback recovers. It could also happen, if you are scrubbing in the timeline, especially to areas not loaded already (progressive MP4 download). Behaviour is always the same: image is stalled/frozen, audio goes on. To reproduce: use example project https://developer.apple.com/documentation/AVKit/playing-video-content-in-a-standard-user-interface Example file: https://www.keepinmind.info/test.mp4

I’m building a macOS video editor that uses AVComposition and AVVideoComposition. Initially, my renderer creates a composition with some default video/audio tracks: @Published var composition: AVComposition? @Published var videoComposition: AVVideoComposition? @Published var playerItem: AVPlayerItem? Then I call a buildComposition() function that inserts all the default video segments. Later in the editing workflow, the user may choose to add their own custom video clip. For this I have a function like: private func handlePickedVideo(_ url: URL) { guard url.startAccessingSecurityScopedResource() else { print("Failed to access security-scoped resource") return } let asset = AVURLAsset(url: url) let videoTracks = asset.tracks(withMediaType: .video) guard let firstVideoTrack = videoTracks.first else { print("No video track found") url.stopAccessingSecurityScopedResource() return } renderer.insertUserVideoTrack(from: asset, track: firstVideoTrack) url.stopAccessingSecurityScopedResource() } What I want to achieve is the same behavior professional video editors provide, after the composition has already been initialized and built, the user should be able to add a new video track and the composition should update live, meaning the preview player should immediately reflect the changes without rebuilding everything from scratch manually. How can I structure my AVComposition / AVMutableComposition and my rendering pipeline so that adding a new clip later updates the existing composition in real time (similar to Final Cut/Adobe Premiere), instead of needing to rebuild everything from zero? You can find a playable version of this entire setup at :- https://github.com/zaidbren/SimpleEditor

I believe this should work: CFMutableDictionaryRef attrs = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks); CFDictionaryAddValue(attrs, kCVImageBufferColorPrimariesKey, kCVImageBufferColorPrimaries_ITU_R_709_2); CFDictionaryAddValue(attrs, kCVImageBufferTransferFunctionKey, kCVImageBufferTransferFunction_ITU_R_709_2); CFDictionaryAddValue(attrs, kCVImageBufferYCbCrMatrixKey, kCVImageBufferYCbCrMatrix_ITU_R_709_2); CVPixelBufferRef pixelBuffer = NULL; CVPixelBufferCreate(kCFAllocatorDefault, width, height, kCVPixelFormatType_32ARGB, attrs, &pixelBuffer); assert(CFDictionaryGetCount(CVBufferGetAttachments(pixelBuffer, kCVAttachmentMode_ShouldPropagate)) > 0); But that last assert fails, so it appears the color info does not get attached. kCVImageBufferColorPrimariesKey and the others are not one of the keys listed under BufferAttributeKeys, but I think they're supposed to be allowed because they're listed by CMVideoFormatDescriptionGetExtensionKeysCommonWithImageBuffers(). I'm hoping that putting the color matrix info in there will control how AVAssetWriter converts the RGB to YCbCr.

I want to confirm if this is a bug or a programming error. Very easy to reproduce it by modifying AVCam sample code. Steps to reproduce: Add AVCaptureVideoDataOutput to AVCaptureSession, no need to set delegate in AVCam sample code (CaptureService actor) private let videoDataOutput = AVCaptureVideoDataOutput() and then in configureSession method, add the following line try addOutput(videoDataOutput) if videoDataOutput.availableVideoPixelFormatTypes.contains(kCVPixelFormatType_420YpCbCr8BiPlanarFullRange) { videoDataOutput.videoSettings = [kCVPixelBufferPixelFormatTypeKey as AnyHashable as! String : kCVPixelFormatType_420YpCbCr8BiPlanarFullRange] } And next modify set HDR method: /// Sets whether the app captures HDR video. func setHDRVideoEnabled(_ isEnabled: Bool) { // Bracket the following configuration in a begin/commit configuration pair. captureSession.beginConfiguration() defer { captureSession.commitConfiguration() } do { // If the current device provides a 10-bit HDR format, enable it for use. if isEnabled, let format = currentDevice.activeFormat10BitVariant { try currentDevice.lockForConfiguration() currentDevice.activeFormat = format currentDevice.unlockForConfiguration() isHDRVideoEnabled = true if videoDataOutput.availableVideoPixelFormatTypes.contains(kCVPixelFormatType_420YpCbCr10BiPlanarVideoRange) { videoDataOutput.videoSettings = [kCVPixelBufferPixelFormatTypeKey as AnyHashable as! String : kCVPixelFormatType_420YpCbCr10BiPlanarVideoRange] } } else { captureSession.sessionPreset = .high isHDRVideoEnabled = false if videoDataOutput.availableVideoPixelFormatTypes.contains(kCVPixelFormatType_32BGRA) { print("Setting sdr pixel format \(kCVPixelFormatType_32BGRA)") videoDataOutput.videoSettings = [kCVPixelBufferPixelFormatTypeKey as AnyHashable as! String : kCVPixelFormatType_32BGRA] } try currentDevice.lockForConfiguration() currentDevice.activeColorSpace = .sRGB currentDevice.unlockForConfiguration() } } catch { logger.error("Unable to obtain lock on device and can't enable HDR video capture.") } The problem now is toggling HDR on and off no longer works in video mode. If after setting HDR on, you set HDR to off, active format of device does not change (setting sessionPreset has no effect). This does not happen if video data output is not added to session. Is there any workaround available?

Avplayer encapsulates a player. After connecting to an Apple Bluetooth headset, it immediately reports an error. Non-Apple Bluetooth headsets can be played, but currently the issue is that the player works normally in one app but not in another. We are an educational app.