Hi, I am working on an app that is very similar to TikTok in terms of video experience. There is an infinite scroll feed of videos, and I am using HLS URLs as the video source. My requirement is to cache the initial few seconds of each video on the disk while the video is playing. The next time a user views the video, it should play the initial few seconds from the cache, with the subsequent chunks coming from the network. Additionally, when there is no network connection, the video should still play the initial few seconds from the cache. I was able to achieve this with MP4 using AVAssetResourceLoaderDelegate, but the same approach is not possible with HLS. What are some other ways through which I can implement this feature? Thanks.

I'm trying to cast the screen from an iOS device to an Android device. I'm leveraging ReplayKit on iOS to capture the screen and VideoToolbox for compressing the captured video data into H.264 format using CMSampleBuffers. Both iOS and Android are configured for H.264 compression and decompression. While screen casting works flawlessly within the same platform (iOS to iOS or Android to Android), I'm encountering an error ("not in avi mode") on the Android receiver when casting from iOS. My research suggests that the underlying container formats for H.264 might differ between iOS and Android. Data transmission over the TCP socket seems to be functioning correctly. My question is: Is there a way to ensure a common container format for H.264 compression and decompression across iOS and Android platforms? Here's a breakdown of the iOS sender details: Device: iPhone 13 mini running iOS 17 Development Environment: Xcode 15 with a minimum deployment target of iOS 16 Screen Capture: ReplayKit for capturing the screen and obtaining CMSampleBuffers Video Compression: VideoToolbox for H.264 compression Compression Properties: kVTCompressionPropertyKey_ConstantBitRate: 6144000 (bitrate) kVTCompressionPropertyKey_ProfileLevel: kVTProfileLevel_H264_Main_AutoLevel (profile and level) kVTCompressionPropertyKey_MaxKeyFrameInterval: 60 (maximum keyframe interval) kVTCompressionPropertyKey_RealTime: true (real-time encoding) kVTCompressionPropertyKey_Quality: 1 (lowest quality) NAL Unit Handling: Custom header is added to NAL units Android Receiver Details: Device: RedMi 7A running Android 10 Video Decoding: MediaCodec API for receiving and decoding the H.264 stream

I am a bit confused on whether certain Video Toolbox (VT) encoders support hardware acceleration or not. When I query the list of VT encoders (VTCopyVideoEncoderList(nil,&encoderList)) on an iPhone 14 Pro device, for avc1 (AVC / H.264) and hevc1 (HEVC / H.265) encoders, the kVTVideoEncoderList_IsHardwareAccelerated flag is not there, which -based on the documentation found on the VTVideoEncoderList.h- means that the encoders do not support hardware acceleration: optional. CFBoolean. If present and set to kCFBooleanTrue, indicates that the encoder is hardware accelerated. In fact, no encoders from this list return this flag as true and most of them do not include the flag at all on their dictionaries. On the other hand, when I create a compression session using the VTCompressionSessionCreate() and pass the kVTVideoEncoderSpecification_EnableHardwareAcceleratedVideoEncoder as true in the encoder specifications, after querying the kVTCompressionPropertyKey_UsingHardwareAcceleratedVideoEncoder using the following code, I get a CFBoolean value of true for both H.264 and H.265 encoder. In fact, I get a true value (for both of the aforementioned encoders) even if I don't specify the kVTVideoEncoderSpecification_EnableHardwareAcceleratedVideoEncoder during the creation of the compression session (note here that this flag was introduced in iOS 17.4 ^1). So the question is: Are those encoders actually hardware accelerated on my device, and if so, why isn't that reflected on the VTCopyVideoEncoderList() call?

I have been seeing some crash reports for my app on some devices (not all of them). The crash occurs while converting a CVPixelBuffer captured from Video to a JPG using VTCreateCGImageFromCVPixelBuffer from VideoToolBox. I have not been able to reproduce the crash on local devices, even under adverse memory conditions (many apps running in the background). The field crash reports show that VTCreateCGImageFromCVPixelBuffer does the conversion in another thread and that thread crashed at call to vConvert_420Yp8_CbCr8ToARGB8888_vec. Any suggestions on how to debug this further would be helpful.

xtension Entity { func addPanoramicImage(for media: WRMedia) { let subscription = TextureResource.loadAsync(named:"image_20240425_201630").sink( receiveCompletion: { switch $0 { case .finished: break case .failure(let error): assertionFailure("(error)") } }, receiveValue: { [weak self] texture in guard let self = self else { return } var material = UnlitMaterial() material.color = .init(texture: .init(texture)) self.components.set(ModelComponent( mesh: .generateSphere(radius: 1E3), materials: [material] )) self.scale *= .init(x: -1, y: 1, z: 1) self.transform.translation += SIMD3(0.0, -1, 0.0) } ) components.set(Entity.WRSubscribeComponent(subscription: subscription)) } func updateRotation(for media: WRMedia) { let angle = Angle.degrees( 0.0) let rotation = simd_quatf(angle: Float(angle.radians), axis: SIMD3<Float>(0, 0.0, 0)) self.transform.rotation = rotation } struct WRSubscribeComponent: Component { var subscription: AnyCancellable } } case .failure(let error): assertionFailure("(error)") Thread 1: Fatal error: Error Domain=MTKTextureLoaderErrorDomain Code=0 "Image decoding failed" UserInfo={NSLocalizedDescription=Image decoding failed, MTKTextureLoaderErrorKey=Image decoding failed}

I have a AVPlayer() which loads the video and places it on the screen ModelEntity in the immersive view using the VideoMaterial. This also makes the video untappable as it is a VideoMaterial. Here's the code for the same: let screenModelEntity = model.garageScreenEntity as! ModelEntity let modelEntityMesh = screenModelEntity.model!.mesh let url = Bundle.main.url(forResource: "<URL>", withExtension: "mp4")! let asset = AVURLAsset(url: url) let playerItem = AVPlayerItem(asset: asset) let player = AVPlayer() let material = VideoMaterial(avPlayer: player) screenModelEntity.components[ModelComponent.self] = .init(mesh: modelEntityMesh, materials: [material]) player.replaceCurrentItem(with: playerItem) return player I was able to load and play the video. However, I cannot figure out how to show the player controls (AVPlayerViewController) to the user, similar to the DestinationVideo sample app. How can I add the video player controls in this case?

I am Using VideoToolbox VTCompressionSession For Encoding The Frame in H264 Format Which I will send through web socket to a browser. The Received Frames Will be Decoded and Output Will be rendered in the Website. Now, when using Some encoders the video is rendered always with four frame latency. How Frame is sent to server : start>------------ f1 ------------ f2 ------------ f3 ------------ f4 ------------- f5 ... How rendering is happening : start>-------------------------------------------------------------------------- f1 ------------ f2 ------------ f3 ------------ f4 ----------- ... This Sometime becomes two frame latency and Sometime it becomes sixteen frame latency so the usability is getting affected. Im using this configuration in videotoolbox's VTCompressionSession: kVTCompressionPropertyKey_AverageBitRate=3MB kVTCompressionPropertyKey_ExpectedFrameRate=24 kVTCompressionPropertyKey_RealTime=true kVTCompressionPropertyKey_ProfileLevel=kVTProfileLevel_H264_High_AutoLevel kVTCompressionPropertyKey_AllowFrameReordering = false kVTCompressionPropertyKey_MaxKeyFrameInterval=1000 With Same Configuration i am able to achieve 1 in - 1 out with com.apple.videotoolbox.videoencoder.h264.gva. This Issue Is replication with Encoder com.apple.videotoolbox.videoencoder.ave.avc Not Sure if its Encoder Specific. I have also seen that there are difference in VUI Parameters between encoded output of both encoders. I want to know if there is something i could do to solve this issue from the Encoder Configuration or another API which is provided by the VideoToolBox to ensure that frames are decoded and rendered at the same time by Decoder. Thanks in Advance....

So I've been trying for weeks now to implement a compression mechanism into my app project that compresses MV-HEVC video files in-app without stripping videos of their 3D properties, but every single implementation I have tried has either stripped the encoded MV-HEVC video file of its 3D properties (making the video monoscopic), or has crashed with a fatal error. I've read the Reading multiview 3D video files and Converting side-by-side 3D video to multiview HEVC documentation files, but was unable to myself come out with anything useful. My question therefore is: How do you go about compressing/encoding an MV-HEVC video file in-app whilst preserving the stereoscopic/3D properties of that MV-HEVC video file? Below is the best implementation I was able to come up with (which simply compresses uploaded MV-HEVC videos with an arbitrary bit rate). With this implementation (my compressVideo function), the MV-HEVC files that go through it are compressed fine, but the final result is the loss of that MV-HEVC video file's stereoscopic/3D properties. If anyone could point me in the right direction with anything it would be greatly, greatly appreciated. My current implementation (that strips MV-HEVC videos of their stereoscopic/3D properties): static func compressVideo(sourceUrl: URL, bitrate: Int, completion: @escaping (Result<URL, Error>) -> Void) { let asset = AVAsset(url: sourceUrl) asset.loadTracks(withMediaType: .video) { videoTracks, videoError in guard let videoTrack = videoTracks?.first, videoError == nil else { completion(.failure(videoError ?? NSError(domain: "VideoUploader", code: -1, userInfo: [NSLocalizedDescriptionKey: "Failed to load video track"]))) return } asset.loadTracks(withMediaType: .audio) { audioTracks, audioError in guard let audioTrack = audioTracks?.first, audioError == nil else { completion(.failure(audioError ?? NSError(domain: "VideoUploader", code: -2, userInfo: [NSLocalizedDescriptionKey: "Failed to load audio track"]))) return } let outputUrl = sourceUrl.deletingLastPathComponent().appendingPathComponent(UUID().uuidString).appendingPathExtension("mov") guard let assetReader = try? AVAssetReader(asset: asset), let assetWriter = try? AVAssetWriter(outputURL: outputUrl, fileType: .mov) else { completion(.failure(NSError(domain: "VideoUploader", code: -3, userInfo: [NSLocalizedDescriptionKey: "AssetReader/Writer initialization failed"]))) return } let videoReaderSettings: [String: Any] = [kCVPixelBufferPixelFormatTypeKey as String: kCVPixelFormatType_32ARGB] let videoSettings: [String: Any] = [ AVVideoCompressionPropertiesKey: [AVVideoAverageBitRateKey: bitrate], AVVideoCodecKey: AVVideoCodecType.hevc, AVVideoHeightKey: videoTrack.naturalSize.height, AVVideoWidthKey: videoTrack.naturalSize.width ] let assetReaderVideoOutput = AVAssetReaderTrackOutput(track: videoTrack, outputSettings: videoReaderSettings) let assetReaderAudioOutput = AVAssetReaderTrackOutput(track: audioTrack, outputSettings: nil) if assetReader.canAdd(assetReaderVideoOutput) { assetReader.add(assetReaderVideoOutput) } else { completion(.failure(NSError(domain: "VideoUploader", code: -4, userInfo: [NSLocalizedDescriptionKey: "Couldn't add video output reader"]))) return } if assetReader.canAdd(assetReaderAudioOutput) { assetReader.add(assetReaderAudioOutput) } else { completion(.failure(NSError(domain: "VideoUploader", code: -5, userInfo: [NSLocalizedDescriptionKey: "Couldn't add audio output reader"]))) return } let audioInput = AVAssetWriterInput(mediaType: .audio, outputSettings: nil) let videoInput = AVAssetWriterInput(mediaType: .video, outputSettings: videoSettings) videoInput.transform = videoTrack.preferredTransform assetWriter.shouldOptimizeForNetworkUse = true assetWriter.add(videoInput) assetWriter.add(audioInput) assetReader.startReading() assetWriter.startWriting() assetWriter.startSession(atSourceTime: CMTime.zero) let videoInputQueue = DispatchQueue(label: "videoQueue") let audioInputQueue = DispatchQueue(label: "audioQueue") videoInput.requestMediaDataWhenReady(on: videoInputQueue) { while videoInput.isReadyForMoreMediaData { if let sample = assetReaderVideoOutput.copyNextSampleBuffer() { videoInput.append(sample) } else { videoInput.markAsFinished() if assetReader.status == .completed { assetWriter.finishWriting { completion(.success(outputUrl)) } } break } } } audioInput.requestMediaDataWhenReady(on: audioInputQueue) { while audioInput.isReadyForMoreMediaData { if let sample = assetReaderAudioOutput.copyNextSampleBuffer() { audioInput.append(sample) } else { audioInput.markAsFinished() break } } } } } }

Hello, I've noticed that my server-hosted video that is larger than 19 MB doesn't work on iOS mobile devices. What is the maximum size limit (in MB) for the video html tag on iOS mobile devices?

How Can I update the cookies of the previously set m3u8 video in AVPlayer without creating the new AVURLAsset and replacing the AVPlayer current Item with it

Does the new MV-HEVC vision pro spatial video format supports having an alpha channel? I've tried converting a side by side video with alpha channel enabled by using this Apple example project, but the alpha channel is being removed. https://developer.apple.com/documentation/avfoundation/media_reading_and_writing/converting_side-by-side_3d_video_to_multiview_hevc

Hi everyone, I need to add spatial video maker in my app which was wrote in objective-c. I found some reference code by swift, can you help me with converting the code to objective -c? let left = CMTaggedBuffer( tags: [.stereoView(.leftEye), .videoLayerID(leftEyeLayerIndex)], pixelBuffer: leftEyeBuffer) let right = CMTaggedBuffer( tags: [.stereoView(.rightEye), .videoLayerID(rightEyeLayerIndex)], pixelBuffer: rightEyeBuffer) let result = adaptor.appendTaggedBuffers( [left, right], withPresentationTime: leftPresentationTs)

Does Video Toolbox’s compression session yield data I can decompress on a different device that doesn’t have Apple’s decompression? i.e. so I can network data to other devices that aren’t necessarily Apple? or is the format proprietary rather than just regular h.264 (for example)? If I can decompress without video toolbox, may I have reference to some examples for how to do this using cross-platform APIs? Maybe FFMPEG has something?

When I try to play video on my Apple Vision Pro simulator using a custom view with an AVPlayerLayer (as seen in my below VideoPlayerView), nothing displays but a black screen while the audio for the video i'm trying to play plays in the background. I've tried everything I can think of to resolve this issue, but to no avail. import SwiftUI import AVFoundation import AVKit struct VideoPlayerView: UIViewRepresentable { var player: AVPlayer func makeUIView(context: Context) -> UIView { let view = UIView(frame: .zero) let playerLayer = AVPlayerLayer(player: player) playerLayer.videoGravity = .resizeAspect view.layer.addSublayer(playerLayer) return view } func updateUIView(_ uiView: UIView, context: Context) { if let layer = uiView.layer.sublayers?.first as? AVPlayerLayer { layer.frame = uiView.bounds } } } I have noticed however that if i use the default VideoPlayer (as demonstrated below), and not my custom VideoPlayerView, the video displays just fine, but any modifiers I use on that VideoPlayer (like the ones in my above custom struct), cause the video to display black while the audio plays in the background. import SwiftUI import AVKit struct MyView: View { var player: AVPlayer var body: some View { ZStack { VideoPlayer(player: player) Does anyone know a solution to this problem to make it so that video is able to display properly and not just appear as a black screen with audio playing in the background?

Hello, can anybody help me with this ? I am downloading video in FS, and when I give that url to player it gives me this error. but this comes up only in case of m3u8. other format like mp4 are working fine locally. please help ! {"error": {"code": -12865, "domain": "CoreMediaErrorDomain", "localizedDescription": "The operation couldn’t be completed. (CoreMediaErrorDomain error -12865.)", "localizedFailureReason": "", "localizedRecoverySuggestion": ""}, "target": 13367}

Hi, I am looking at display some spatial video content captured on iPhone 15 Pros in a side-by-side format. I've read the HEVC Stereo Video Profile provided by Apple, but I am confused on access the left and right eye video. Looking at the AVAsset track information, there is one video track, one sound, and three metadata ones. Apple's document references them as layers, but I am unsure how to access them. Could anyone provide some guidance on the access of them? Thanks, Will

Who can I contact that can remove the gray frame from around the full screen video player on my iOS mobile application? This is an Apple iOS feature that I have no control over. The screenshot attached below shows the full screen view of a video when the iOS mobile phone is held sideways. The issue is the big gray frame that is around the video, is taking up too much space from the video and it needs to be removed so the video can be fully screened.

I am using the official website API to decode now, the callback did not trigger.

我使用VideoToolBox库进行编码后再通过NDI发送到网络上，是可以成功再苹果电脑上接收到ndi源屏显示画面的，但是在windows上只能ndi源名称，并没有画面显示。 我想知道是不是使用VideoToolBox库无法在windows上进行正确编码，这个问题需要如何解决

Is there a way to play a specific rectangular region of interest of a video in an arbitrarily-sized view? Let's say I have a 1080p video but I'm only interested in a sub-region of the full frame. Is there a way to specify a source rect to be displayed in an arbitrary view (SwiftUI view, ideally), and have it play that in real time, without having to pre-render the cropped region? Update: I may have found a solution here: img DOT ly/blog/trim-and-crop-video-in-swift/ (Apple won't allow that URL for some dumb reason)