My app currently captures video using an AVCaptureSession set with the AVCaptureSessionPreset1920x1080 preset. However, I'd like to update this behavior, such that video can be recorded at a range of different resolutions. There isn't a preset aligning to each desired resolution, so I thought I'd instead directly set the AVCaptureDeviceFormat. For any desired resolution, I would find the format that is closest without going under the desired resolution, and then crop it down as a post-processing step. However, what I've observed is that there can be a range of available formats for a device at each resolution, with various differing settings. Presumably there is logic within AVCaptureSession that selects a reasonable default based on all these different settings, but since I am applying the format directly, I think I don't have a way to make use of that default logic? And it is undocumented? Does this mean that the only way to select a format is to implement a comparison function that considers all different values of all different properties on AVCaptureDeviceFormat, and then sort the formats according to this comparator? If so, what if some new property is added to AVCaptureDeviceFormat in the future? The sort would not take this new property into account, and the function might select a format with some new undesired property. Are there any guarantees about what types for formats will be supported on a device? For example, can I take for granted that a '420v' format will exist at each resolution? If so I could filter the formats down only to those with this setting without risking filtering out all of the supported formats. I suspect I may be missing something obvious. Any help would be greatly appreciated!

Hi everyone, I just upgraded my iPhone to 18.1.1. I noticed the absence of the normal mode on my AirPods. I can't stand the noise cancellation mode for too long and the transparency one is overwhelming everytime a hair is brushing near by my AirPods. Why is that? I don't really see the progression here. Can you this be fixed in the next version? I don't want to buy another brand, I use them everyday for many hours.

When trying to edit some Live Photos, calling PHLivePhotoEditingContext.saveLivePhoto results in the following error: Error Domain=AVFoundationErrorDomain Code=-11800 "The operation could not be completed" UserInfo={NSLocalizedFailureReason=An unknown error occurred (-12815), NSLocalizedDescription=The operation could not be completed, NSUnderlyingError=0x300d05380 {Error Domain=NSOSStatusErrorDomain Code=-12815 "(null)"}} I was able to replicate it on my device by taking a new Live Photo. Not sure what's wrong with that one specifically, not all Live Photos replicate the issue. I've submitted FB15880825 with a sysdiagnose and a Photos Diagnostics as well. Any ideas what's going on here? It's impacting multiple customers. Thanks!

Since iOS/iPadOs/tvOS 18 then we have run into a new problem with streaming of FairPlay encrypted video. On the affected streams then the audio plays perfectly but the video freezes for periods of a few seconds, so it will freeze for 5s or so, then be OK for a few seconds then freeze again. It is entirely reproducible when all the following are true the video streams were produced by a particular encoder (or particular settings, not sure on that) the video must be encrypted device is running some variety of iOS 18 (or iPadOS or tvOS) the device is an affected device Known devices are AppleTV 4K 2nd Gen iPad Pro 11" 1st and 2nd gen Devices known not to show the problem are all other AppleTV models iPhone 13 Pro and 16 Pro If we stream the same content, but unencrypted, then it plays perfectly, or if you play the encrypted stream on, say, tvOS 17. When the freezing occurs then we can see in the console logs repeating blocks of lines like the following default 18:08:46.578582+0000 videocodecd AppleAVD: AppleAVDDecodeFrameResponse(): Frame# 5771 DecodeFrame failed with error 0x0000013c default 18:08:46.578756+0000 videocodecd AppleAVD: AppleAVDDecodeFrameInternal(): failed - error: 316 default 18:08:46.579018+0000 videocodecd AppleAVD: AppleAVDDecodeFrameInternal(): avdDec - Frame# 5771, DecodeFrame failed with error: 0x13c default 18:08:46.579169+0000 videocodecd AppleAVD: AppleAVDDisplayCallback(): Asking fig to drop frame # 5771 with err -12909 - internalStatus: 315 also more relevant looking lines: default 18:17:39.122019+0000 kernel AppleAVD: avdOutbox0ISR(): FRM DONE (cid: 2.0, fno: 10970, codecT: 1) FAILED!! default 18:17:39.122155+0000 videocodecd AppleAVD: AppleAVDDisplayCallback(): Asking fig to drop frame # 10970 with err -12909 - internalStatus: 315 default 18:17:39.122221+0000 kernel AppleAVD: ## client[ 2.0] @ frm 10970, errStatus: 0x10 default 18:17:39.122338+0000 kernel AppleAVD: decodeFailIdentify(): VP error bit 4 has EP3B0 error default 18:17:39.122401+0000 kernel AppleAVD: processHWResponse(): clientID 2.0 frameNumber 10970 error 315, offsetIndex 10, isHwErr 1 So it would seem to me that one of the following must be happening: When these particular HLS files are encrypted then the data is being corrupted in some way that played back on iOS 17 and earlier but now won't on 18+, or There's a regression in iOS 18 that means that this particular format of video data is corrupted on decryption If anyone has seen similar behaviour, or has any ideas how to identify which of the two scenarios it is, please say. Unfortunately we don't have control of the servers so can't make changes there unless we can identify they are definitely the cause of the problem. Thanks, Simon.

Our app involves using the camera to scan barcodes or QR codes, with a working distance of about 5 cm. However, we’ve noticed variations in the focus distance of camera lenses across different iPhone models. Currently, we mainly use two types of lenses: wide-angle and ultra-wide-angle. • For iPhone 13 and earlier models, we use the wide-angle lens. • For iPhone 13 Pro and later models, we use the ultra-wide-angle lens. We are not certain if this setup is correct since we don’t have all iPhone models to test.
There is a users have reported focus issues on his iPhone 15. We would like to ask if there’s a resource where we can find the minimum focus distance of different cameras in each iPhone model. This is to verify whether our current configuration is accurate. Alternatively, if such data is not readily available, could apple tam advise which camera should be used on various iPhone models for scenarios with a working distance of approximately 5 cm? Thank you!

I'm trying to implement anti-spoofing in iOS app using iphone true depth front camera. I have checked the following questions still can't find a proper working solution. I trained a coreML model using 22000 depth human face images and 22000 non-human face(objects,food etc) images. The accuracy of the model is very less. When testing out with flat 2d images shown on a smartphone screen I found that I get depth map even for flat 2D images like this. Even though the image is flat how does it give the depth map for the person shown in the flat 2D picture so the model thinks that it is a real face instead of a spoofed one. I implemented depth capture by following this documentation and I made sure that I get depth map instead of disparity map https://developer.apple.com/documentation/avfoundation/additional_data_capture/capturing_photos_with_depth My next approach was to use NCNN framework to implement anti-spoofing by using the model used in the Mini-vision android anti-spoofing sample. I rewrote their library in iOS by using the objective C++ wrapper for C++ as the sample was only available for android app. And I tested by feeding 80x80 UI-Image in a open cv matrix format it's accurracy is less than the android one. How can I solve this problem.

I'm building a custom camera screen that displays the camera image on a preview layer and then captures an image, using AVCaptureSession. When the picture is captured, I immediately load it into a UIImageView in order to display it to the user for approval. I've actually done this many times before, but this is the first time I've tried to do it in an app that supports interface rotation. If I hold the phone in Portrait mode and capture a picture, everything works as expected. When the user rotates the phone into Landscape orientation, I detect this and I replace the preview layer (AVCaptureVideoPreviewLayer) with a new one, specifying connection.videoRotationAngle in order to make the image appear in the right orientation. I'm a little surprised that this is necessary, and it's not a smooth transition, but that doesn't matter. What does matter is that when I capture the image, it is in the wrong orientation. I tried rotating it myself, but this doesn't seem to make any difference. What am I doing wrong?

Description As of iOS 18, AVAudioSession.setPreferredIOBufferDuration ignores the requested buffer size when Sound Recognition or Vocal Shortcuts is enabled. This results in 1) much larger buffer sizes and 2) mismatched buffer sizes between input and output buffers, which causes ‘glitchy’ audio and increased latency. Additionally, when this issue occurs AVAudioSession.setPreferredIOBufferDuration continues to return ‘true’ and no error is produced. Steps to Reproduce: Enable Vocal Shortcuts on a device running iOS 18. Enable at least one shortcut (e.g. Control Center). Open or clone the example project (https://github.com/cwalo/SoundRecognitionBug) Build and install the example project Attach a headset and launch the application Observe console logs showing a requested buffer size of 0.005805 (256 samples @ 48k) an actual buffer size of 0.023220 (1104 samples @48k - this is regularly the resulting buffer size in all of our tests) Quit the app and detach the headset. Enable mutesOutput in AudioSystem.mm (to avoid feedback) Launch the application Observe Same result from step 4 Mismatched hardware buffer size of 1104 and recorded frame count of 1024 Mismatched playbackCount and recordCount Quit the app and disable vocal shortcuts Launch the app Observe IOBufferDuration matching the requested duration and matched buffer sizes (expected behavior) Expected results: Requested IOBufferDuration is respected or AVAudioSession returns false or error is produced Input and output buffer sizes match Device(s): iPhone 11 Pro, iPad Pro OS: iOS 18.0.1 Environment: Xcode 16.1 FB: FB15715421 Related to: https://forums.developer.apple.com/forums/thread/765477

For an upcoming update of one of my apps, I’m facing an issue: The .rate parameter of a AVAudioUnitTimePitch allows me to slow down an audio track without any issues: setting .rate to 0.7 or 0.8 results in an almost perfect playback without changing pitch. However, whenever the .rate parameter is greater than 1 (e.g. 1.1 or 1.15), I’m starting to hear audio artifacts (“flattering”) in the audio output which is not so nice (even at .overlap = 32). Intuitively, I’d’ve thought that speeding up the file should contain less artifacts than slowing it down?? I’ve tried different sample rates (44.1 kHz and 48 kHz), but same result. Grateful for any input on this 🙏

Capturing more than one display is no longer working with macOS Sequoia. We have a product that allows users to capture up to 2 displays/screens. Our application is using gstreamer which in turn is based on AVFoundation. I found a quick way to replicate the issue by just running 2 captures from separate terminals. Assuming display 1 has device index 0, and display 2 has device index 1, here are the steps: install gstreamer with brew install gstreamer Then open 2 terminal windows and launch the following processes: terminal 1 (device-index:0): gst-launch-1.0 avfvideosrc -e device-index=0 capture-screen=true ! queue ! videoscale ! video/x-raw,width=640,height=360 ! videoconvert ! osxvideosink terminal 2 (device-index:1): gst-launch-1.0 avfvideosrc -e device-index=1 capture-screen=true ! queue ! videoscale ! video/x-raw,width=640,height=360 ! videoconvert ! osxvideosink The first process that is launched will show the screen, the second process launched will not. Testing this on macOS Ventura and Sonoma works as expected, showing both screens. I submitted the same issue on Feedback Assistant: FB15900976

Issue Description When playing certain MIDI files using AVMIDIPlayer, the initial volume settings for individual tracks are being ignored during the first playback. This results in all tracks playing at the same volume level, regardless of their specified volume settings in the MIDI file. Steps to Reproduce Load a MIDI file that contains different volume settings for multiple tracks Start playback using AVMIDIPlayer Observe that all tracks play at the same volume level, ignoring their individual volume settings Current Behavior All tracks play at the same volume level during initial playback Track volume settings specified in the MIDI file are not being respected This behavior consistently occurs on first playback of affected MIDI files Expected Behavior Each track should play at its specified volume level from the beginning Volume settings in the MIDI file should be respected from the first playback Workaround I discovered that the correct volume settings can be restored by: Starting playback of the MIDI file Setting the currentPosition property to (current time - 1 second) After this operation, all tracks play at their intended volume levels However, this is not an ideal solution as it requires manual intervention and may affect the playback experience. Questions Is there a way to ensure the track volume settings are respected during the initial playback? Is this a known issue with AVMIDIPlayer? Are there any configuration settings or alternative approaches that could resolve this issue? Technical Details iOS Version: 18.1.1 (22B91) Xcode Version: 16.1 (16B40)

Within my app, I have: for try await update in LockedCameraCaptureManager.shared.sessionContentUpdates { It seems that the first time my app opens from LockedCameraCapture (after enabling camera permissions etc...) this update is never called and the user will not see their capture (.added or .initial) If I then try to take another picture/video through my LockedCameraCapture control, it takes the video, opens the app as before, but this time sessionContentUpdates is called twice, once for the first video and once for the second video! After that it doesn't seem to occur again and all works perfectly! My device is: iPhone 16 Pro Max, iOS 18.2 developer beta Has anyone experienced this?

Case-ID: 10075936 PLATFORM AND VERSION iOS Development environment: Xcode Xcode15, macOS macOS 14.5 Run-time configuration: iOS iOS18.0.1 DESCRIPTION OF PROBLEM Our customer experienced an one-way audio issue when switching from the built-in microphone to AirPods Pro (model: A2084, version: 6F21) during a VoIP call. The issue occurred when the customer's voice could not be heard by the other party, but the customer could hear the other party's voice. STEPS TO REPRODUCE Here are the details: After the issue occurred, subsequent VoIP calls experienced the same issue when using AirPods Pro, but the issue did not occur when using the built-in microphone. The issue could only be resolved by restarting the system, and killing the app did not work. Log and code analysis: In WebRTC, it listens for AVAudioSessionRouteChangeNotification. In the above scenario, when webrtc receives the route change notification, it will print the audio session configuration information. At this point, the input channel count was 0, which was abnormal: [Webrtc] (RTCLogging.mm:33): (audio_device_ios.mm:535 HandleValidRouteChange): RTC_OBJC_TYPE(RTCAudioSession): { category: AVAudioSessionCategoryPlayAndRecord categoryOptions: 128 mode: AVAudioSessionModeVoiceChat isActive: 1 sampleRate: 48000.00 IOBufferDuration: 0.020000 outputNumberOfChannels: 2 inputNumberOfChannels: 0 outputLatency: 0.021500 inputLatency: 0.005000 outputVolume: 0.600000 isPreferredSpeaker: 0 isCallkit: 0 } If app tries to call API, setPreferredInputNumberOfChannels at this point, it will fail with an error code of -50: setConfiguration:active:shouldSetActive:error:]): Failed to set preferred input number of channels(1): The operation couldn’t be completed. (OSStatus error -50.) Our questions: When AVAudioSession is active, the category and mode are as expected. Why is the input channel count 0? Assuming that the AVAudioSession state is abnormal at this point, why does killing the app not resolve the issue, and why does the system need to be restarted to resolve the issue? Is it possible that the category and mode of the AVAudioSession fetched by the app is currently wrong? Does it need to be reset again each time the callkit is started if the category and mode fetched are the same as the values to be set?

I have an app that allows the user to change a photo’s EXIF metadata. To do this, I request a content editing input, get the full size image, modify its properties, create a content editing output, write the output image to the rendered content URL, then call performChanges on the PHPhotoLibrary creating an asset change request for that asset setting its content editing output. This works as expected for regular photos but Live Photos get turned off converted to a regular photo. To address this, I’m doing something similar by changing the properties of the .photo image in the Live Photo. I detect when the content editing input has a Live Photo, create a Live Photo editing context, set a frame processor that returns the frame’s image after setting its properties to the updated properties when the frame type is photo, then I create the content editing output and save the Live Photo to that output. It modifies the Live Photo successfully, but the metadata is not updated. If you get the full size image again the properties are the original properties. If you look at the EXIF metadata using an app like Metapho it remains unchanged. What am I doing wrong here? Thanks! let imageURL = contentEditingInput.fullSizeImageURL! let inputImage = CIImage(contentsOf: imageURL, options: [.applyOrientationProperty: true])! var metadata: [AnyHashable: Any] = inputImage.properties // Edit the metadata as desired... let editingContext = PHLivePhotoEditingContext(livePhotoEditingInput: contentEditingInput)! editingContext.frameProcessor = { frame, error -> CIImage? in // Edit only the still photo if frame.type == .photo { return frame.image.settingProperties(metadata) } return frame.image } let contentEditingOutput = try await withCheckedThrowingContinuation { continuation in let editingOutput = PHContentEditingOutput(contentEditingInput: contentEditingInput) editingOutput.adjustmentData = adjustmentData editingContext.saveLivePhoto(to: editingOutput) { success, error in if success { continuation.resume(returning: editingOutput) } else { continuation.resume(throwing: error!) } } } try await PHPhotoLibrary.shared().performChanges { let request = PHAssetChangeRequest(for: asset) request.contentEditingOutput = contentEditingOutput }

Hi All, I'm working on a camera system extension where the main app is supposed to transfer a video stream using IOSurface memory sharing to the cam extension. I have built a sample app that does contains all the logic, but without a camera extension. So I'm essentially using IOSurface to render a video in one SwiftUI view and show the result in another SwiftUI view. Just for testing purposes. And everything works fine so far. Now, when moving the receiver code to the camera extensions, I'm having problems in accessing the IOSurface via ID. I am sharing the IOSurface ID via UserDefaults. I know from the logs the ID is correctly transferred. Here is the code that uses IOSurfaceLookup to get the IOSurface. But this fails with the given message. The error message prints the surface ID which is the correct one. I know this from the main app where I get the ID and print it as well. private var surfaceId: Int = -1 { didSet { logger.info("surfaceId has changed") if surfaceId == -1 { stopReceivingFrames() ioSurface = nil } else { guard let surface = IOSurfaceLookup(IOSurfaceID(surfaceId)) else { logger.error("failed to lookup IOSurface with ID: \(self.surfaceId)") return } self.ioSurface = surface logger.info("surface set, now starting receiving frames") startReceivingFrames() } } } My gut feeling says that this issue might be related to some missing entitlement, sandboxing. In general, I have a working camera extension. I'm just not able to render a video in the main app, and send it over to the camera extension to overlay another web cam. Both, the main app and camera extension are in the same XCode workspace and share the same AppGroup. In short, my actual questions are: Is there any entitlement required for using IOSurface between app and camera system extension? Is using IOSurface actually possible in system extensions? Is there any specific setting/requirement that I need to handle to make this work?

I am experiencing an issue while recording audio using AVAudioEngine with the installTap method. I convert the AVAudioPCMBuffer to Data and send it to a UDP server. However, when I receive the Data and play it back, there is continuous crackling noise during playback. I am sending audio data using this library "https://github.com/mindAndroid/swift-rtp" by creating packet and send it. Please help me resolve this issue. I have attached the code reference that I am currently using. Thank you. ViewController.swift

Hello, I'm fairly new to AVAudioEngine and I'm trying to connect 2 mono nodes as left/right input to a stereo node. I was successful in splitting the input audio to 2 mono nodes using AVAudioConnectionPoint and channelMap. But I can't figure out how to connect them back to a stereo node. I'll post the code I have so far. The use case for this is that I'm trying to process the left/right channels with separate audio units. Any ideas? let monoFormat = AVAudioFormat(standardFormatWithSampleRate: nativeFormat.sampleRate, channels: 1)! let leftInputMixer = AVAudioMixerNode() let rightInputMixer = AVAudioMixerNode() let leftOutputMixer = AVAudioMixerNode() let rightOutputMixer = AVAudioMixerNode() let channelMixer = AVAudioMixerNode() [leftInputMixer, rightInputMixer, leftOutputMixer, rightOutputMixer, channelMixer].forEach { engine.attach($0) } let leftConnectionR = AVAudioConnectionPoint(node: leftInputMixer, bus: 0) let rightConnectionR = AVAudioConnectionPoint(node: rightInputMixer, bus: 0) plugin.leftInputMixer = leftInputMixer plugin.rightInputMixer = rightInputMixer plugin.leftOutputMixer = leftOutputMixer plugin.rightOutputMixer = rightOutputMixer plugin.channelMixer = channelMixer leftInputMixer.auAudioUnit.channelMap = [0] rightInputMixer.auAudioUnit.channelMap = [1] engine.connect(previousNode, to: [leftConnectionR, rightConnectionR], fromBus: 0, format: monoFormat) // Process right channel, pass through left channel engine.connect(rightInputMixer, to: plugin.audioUnit, format: monoFormat) engine.connect(plugin.audioUnit, to: rightOutputMixer, format: monoFormat) engine.connect(leftInputMixer, to: leftOutputMixer, format: monoFormat) // Mix back to stereo? engine.connect(leftOutputMixer, to: channelMixer, format: stereoFormat) engine.connect(rightOutputMixer, to: channelMixer, format: stereoFormat)

We are experiencing thousands of crashes in our application when attempting to present the camera through a Web View. The app crashes during this process, and the crash logs point to WebCore::AVVideoCaptureSource::create WebCore::RealtimeMediaSourceCenter::getUserMediaDevices. This issue has only been observed in iOS 18.2 beta versions (beta 1 - 22C5109p, beta 2 - 22C5125e, beta 3 - 22C5131e). In iOS versions below 18.2, the functionality works and we haven't identified any correlation with specific device models. The problem seems to stem from a WebCore framework introduced in these beta releases 18.2. We kindly request a review and fix for this issue in upcoming beta releases to restore functionality. Let us know if there are any workarounds or adjustments we can implement in the interim. Thank you for your attention to this matter.

Hi. I encounter some random crashes of my camera app. After some investigations, I found that it's terminated by the system and the crash log did be generated but the information is not quite useful, and here is the log found via the Console app. Termination & Crash log "Camera not actively used; AVCaptureEventInteraction not installed": Received termination request from [osservice<com.apple.SpringBoard>:10931] on <RBSProcessPredicate <RBSProcessInstancePredicate| [app<com.juniperphoton.PhotonCam]>> with context <RBSTerminateContext| explanation:Capture Application Requirements Unmet: "Camera not actively used; AVCaptureEventInteraction not installed" reportType:CrashLog maxTerminationResistance:Interactive> The crash log exported from the device will have some common information like: It's a EXC_CRASH (SIGKILL) type with no termination reason. Exception Type: EXC_CRASH (SIGKILL) Exception Codes: 0x0000000000000000, 0x0000000000000000 Termination Reason: RUNNINGBOARD 0 It's triggered by the main thread, but it seems to be waiting for an event to process. Triggered by Thread: 0 Thread 0 name: Dispatch queue: com.apple.main-thread Thread 0 Crashed: 0 libsystem_kernel.dylib 0x1ee165788 mach_msg2_trap + 8 1 libsystem_kernel.dylib 0x1ee168e98 mach_msg2_internal + 80 2 libsystem_kernel.dylib 0x1ee168db0 mach_msg_overwrite + 424 3 libsystem_kernel.dylib 0x1ee168bfc mach_msg + 24 4 CoreFoundation 0x19cbe47f4 __CFRunLoopServiceMachPort + 160 5 CoreFoundation 0x19cbe3ea0 __CFRunLoopRun + 1212 6 CoreFoundation 0x19cc36274 CFRunLoopRunSpecific + 588 7 GraphicsServices 0x1e9d6d4c0 GSEventRunModal + 164 8 UIKitCore 0x19f783480 -[UIApplication _run] + 816 9 UIKitCore 0x19f3a9410 UIApplicationMain + 340 10 UIKitCore 0x19fae4bb0 0x19f394000 + 7670704 11 PhotonCam 0x1002e7e3c 0x1002cc000 + 114236 12 dyld 0x1c2d5ade8 start + 2724 Address size fault on the main thread Thread 0 crashed with ARM Thread State (64-bit): ... far: 0x0000000000000000 esr: 0x56000080 Address size fault I have once tried to reproduce this issue when the app is attached with debugger, and it says: Terminated due to signal 9 When the crash or termination happened, the app: No AVCaptureSession is running. The app is in the foreground and users are interacting with some functions like viewing photos or editing photos in the app. When users exit the camera view, like entering the gallery or settings, the camera session will be stopped. Both TestFlight and Debug build will have the same issue. No 3rd party crash reporter is installed(I deliberately disable it in Debug build and TestFlight build) It has adopted the LockedCameraCapture, but current it's running on the main app target(if not, my app will have a button of unlock, so I can confirm about this). Also, when it comes to the memory consumption, there is no JetsamEvent around the crash time. Device and app information Additionally, some information about the tech stack and the current state of my device and my app: iPhone 16 Pro with iOS 18.2 Beta 3. The app is a camera based app(it's PhotonCam and you can find it on the App Store), its main functionality is the camera feature using AVFoundation + Core Image + Metal to deliver camera functionality. It has adopted the Camera Control, AVCaptureEventInteraction and LockedCameraCapture features. If I remember it right, it occurs in iOS 18.1 Release build, but currently I have no such device to confirm. But in iOS 17.x the issue has never happened. Regarding to this termination, on top of my head is the "watchdog" mechanism that will terminate the process that is running on the LockedCameraCapture feature. However I can make sure that currently the app is running as the main target on the home screen. Has anybody encountered this kind of issue and has found some solutions? Thanks in advance.

Hi, I'm developing a musicKit integration in my iOS App, and I want to select songs from recently played (done it), the problem is that the queue is not auto-generated and the user have to select other song if they want to go forward. There is any method to ask for similar songs, or recommended songs, from a song that the user has already selected? It will be really great :) Also if you know it... There is any publisher for the music duration or I need to do a timer?? Thanks. David.