I am trying to develop a music player app with equaliser. I am using AVAudioEngine and attaching AVAudioPlayerNode but when I change the song the previous song is also playing with the current song. Changing multiple song, plays all the song simultaneously. previously I was using MPMediaItemPlayer but in that case I was not able to attach equaliser. I want my app to play one song at a time with equaliser.
self.AVaudioEngine = AVAudioEngine.init()
self.AVaudioPlayerNode = AVAudioPlayerNode.init()
self.AVaudioUnitEQ = AVAudioUnitEQ(numberOfBands: 10)
self.AVaudioEngine.attach(self.AVaudioPlayerNode)
self.AVaudioEngine.attach(self.AVaudioUnitEQ)
self.AVaudioPlayerNode.scheduleFile(self.AVaudioFile, at: nil, completionHandler: nil)
self.AVaudioEngine.connect(self.AVaudioPlayerNode, to: self.AVaudioUnitEQ, format: self.AVaudioFile.processingFormat)
self.AVaudioEngine.connect(self.AVaudioUnitEQ, to: self.AVaudioEngine.mainMixerNode, format: self.AVaudioFile.processingFormat)
if !self.AVaudioEngine.isRunning {
try! self.AVaudioEngine.start()
}
let sampleRate = self.AVaudioFile.processingFormat.sampleRate / 2
let format = self.AVaudioEngine.mainMixerNode.outputFormat(forBus: 0)
self.AVaudioEngine.mainMixerNode.installTap(onBus: 0, bufferSize: AVAudioFrameCount(sampleRate), format: format, block:{ (buffer: AVAudioPCMBuffer!, time: AVAudioTime!) -> Void in
})
self.AVaudioPlayerNode.play()
Thanks in advance!
It`s your code to start playing AVaudioPlayerNode. But, where is your code to stop playing AVaudioPlayerNode?
Have you seen this?
Related
I am building a karaoke app with the ability to sing with video so here is my problem:
I am recording the user video (video only from the front camera) along with applying voice filters with audiokit on a separate audio records.
Now in my playback, i want to play the video and the audio in a sync mode but it didn't succeed because a have an out sync of video and audio.
I am using akplayer for audio so i can apply voice mod and vlckit for playing user video.
do {
//MARK: VLC kit part of the video setup
Vlc_VideoPlayer = VLCMediaPlayer()
Vlc_VideoPlayer.media = VLCMedia(url: recordVideoURL)
Vlc_VideoPlayer.addObserver(self, forKeyPath: "time", options: [], context: nil)
Vlc_VideoPlayer.addObserver(self, forKeyPath: "remainingTime", options: [], context: nil)
Vlc_VideoPlayer.drawable = self.CameraView
//MARK: Audiokit with AKPlayer Setup
file = try AKAudioFile(forReading: recordVoiceURL)
player = AKPlayer(audioFile: file)
self.player.preroll()
delay = AKVariableDelay(player)
delay.rampTime = 0.5
delayMixer = AKDryWetMixer(player, delay)
reverb = AKCostelloReverb(delayMixer)
reverbMixer = AKDryWetMixer(delayMixer, reverb)
booster = AKBooster(reverbMixer)
tracker = AKAmplitudeTracker(booster)
AudioKit.output = tracker
try AudioKit.start()
}catch{
print (error)
}
self.startPlayers()
now the startPlayers function :
func startPlayers(){
DispatchQueue.main.asyncAfter(deadline: .now() + 1) {
if AudioKit.engine.isRunning {
self.Vlc_VideoPlayer.audio.isMuted = true
self.Vlc_VideoPlayer.play()
self.player.isLooping = false
self.player.play()
}else{
self.startPlayers()
}
}
}
I don't know anything about the VLC player, but with the built in AVPlayer there is an option to sync to a clock:
var time: TimeInterval = 1 // 1 second in the future
videoPlayer.masterClock = CMClockGetHostTimeClock()
let hostTime = mach_absolute_time()
let cmHostTime = CMClockMakeHostTimeFromSystemUnits(hostTime)
let cmVTime = CMTimeMakeWithSeconds(time, preferredTimescale: videoPlayer.currentTime().timescale)
let futureTime = CMTimeAdd(cmHostTime, cmVTime)
videoPlayer.setRate(1, time: CMTime.invalid, atHostTime: futureTime)
AKPlayer then supports syncing to the mach_absolute_time() hostTime using its scheduling functions. As you have above, the two will start close together but there is no guarantee of any sync.
Trying to start two players will work out of pure look and unless you have means to synchronize playback after it started, it will not be perfect. Ideally, you should play the audio with VLC as well to make use of its internal synchronization tools.
To iterate on what you have right now, I would suggest to start playback with VLC until it decoded the first frame, pause, start your audio and continue playback with VLC as soon as you decoded the first audio sample. This will still not be perfect, but probably better.
I am having a really difficult time with playing audio in the background of my app. The app is a timer that is counting down and plays bells, and everything worked using the timer originally. Since you cannot run a timer over 3 minutes in the background, I need to play the bells another way.
The user has the ability to choose bells and set the time for these bells to play (e.g. play bell immediately, after 5 minutes, repeat another bell every 10 minutes, etc).
So far I have tried using notifications using DispatchQueue.main and this will work fine if the user does not pause the timer. If they re-enter the app though and pause, I cannot seem to cancel this queue or pause it in anyway.
Next I tried using AVAudioEngine, and created a set of nodes. These will play while the app is in the foreground but seem to stop upon backgrounding. Additionally when I pause the engine and resume later, it won't pause the sequence properly. It will squish the bells into playing one after the other or not at all.
If anyone has any ideas of how to solve my issue that would be great. Technically I could try remove everything from the engine and recreate it from the paused time when the user pauses/resumes, but this seems quite costly. It also doesn't solve the problem of the audio stopping in the background. I have the required background mode 'App plays audio or streams audio/video using Airplay', and it is also checked under the background modes in capabilities.
Below is a sample of how I tried to set up the audio engine. The registerAndPlaySound method is called several other times to create the chain of nodes (or is this done incorrectly?). The code is kinda messy at the moment because I have been trying many ways trying to get this to work.
func setupSounds{
if (attached){
engine.detach(player)
}
engine.attach(player)
attached = true
let mixer = engine.mainMixerNode
engine.connect(player, to: mixer, format: mixer.outputFormat(forBus: 0))
var bell = ""
do {
try engine.start()
} catch {
return
}
if (currentSession.bellObject?.startBell != nil){
bell = (currentSession.bellObject?.startBell)!
guard let url = Bundle.main.url(forResource: bell, withExtension: "mp3") else {
return
}
registerAndPlaySound(url: url, delay: warmUpTime)
}
}
func registerAndPlaySound(url: URL, delay: Double) {
do {
let file = try AVAudioFile(forReading: url)
let format = file.processingFormat
let capacity = file.length
let buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: AVAudioFrameCount(capacity))
do {
try file.read(into: buffer)
}catch {
return
}
let sampleRate = buffer.format.sampleRate
let sampleTime = sampleRate*delay
let futureTime = AVAudioTime(sampleTime: AVAudioFramePosition(sampleTime), atRate: sampleRate)
player.scheduleBuffer(buffer, at: futureTime, options: AVAudioPlayerNodeBufferOptions(rawValue: 0), completionHandler: nil)
player.play()
} catch {
return
}
}
I need to create a Audio Player for streamed URL (m3u8 format). I have created music player using AVPlayer. But I need to show visualizer for streamed song. I have tried different solution but not found any working example of it.
I have created visualizer using AVAudioPlayer(averagePower) but it won't support streamed URL.
Any help to show visualizer for AVPlayer? Thanks in advance.
I have also tried using MYAudioTapProcessor which most of the people suggested, but for streamed URL, tracks always returns null.
Added the MYAudioTapProcessor.h and MYAudioTapProcessor.m in project
//Initialization of player
let playerItem = AVPlayerItem( url:NSURL( string:"https://bitdash-a.akamaihd.net/content/sintel/hls/playlist.m3u8" ) as! URL )
let audioPlayer: AVPlayer = AVPlayer(playerItem:playerItem)
//Added periodic time observer
audioPlayer!.addPeriodicTimeObserver(forInterval: CMTimeMakeWithSeconds(1, 1), queue: DispatchQueue.main) { (CMTime) -> Void in
if audioPlayer!.currentItem?.status == .readyToPlay
{
if let playerItem: AVPlayerItem = audioPlayer!.currentItem {
print(playerItem.asset.tracks.count)
if (playerItem.asset.tracks) != nil {
self.tapProcessor = MYAudioTapProcessor(avPlayerItem: playerItem)
playerItem.audioMix = self.tapProcessor.audioMix
self.tapProcessor.delegate = self
}
}
}
}
//Delegate callback method for MYAudioTapProcessor
func audioTabProcessor(_ audioTabProcessor: MYAudioTapProcessor!, hasNewLeftChannelValue leftChannelValue: Float, rightChannelValue: Float) {
print("volume: \(leftChannelValue) : \(rightChannelValue)")
volumeSlider.value = leftChannelValue
}
Also tried by adding the "Track" observer.
playerItem.addObserver(self, forKeyPath: "tracks", options: NSKeyValueObservingOptions.new, context: nil);
Now if play mp3 file, the callback method calls but for m3u8 callback method doesn't call. The main reason for failing m3u8 URL is it always show tracks array count zero whereas for mp3 files tracks array has one item.
You cannot get tracks for HLS via AVPLayer. You should use progressive download or local file for getting audio tracks while playing media.
I have a simple audio file in .wav format (the audio file is cut perfectly to loop). I've tried different methods to loop it. My first attempt was simply using AVPlayer and NSNotification to detect when audioItem ended to seek time at zero and play again. However, there was clearly a gap.
I've been looking at different solutions online, and found people using AVQueuePlayer to do a switching:
Looping AVPlayer seamlessly
However, when implemented, this still produces a gap.
Here's my current notification code:
weak var weakSelf = self
NSNotificationCenter.defaultCenter().addObserverForName(AVPlayerItemDidPlayToEndTimeNotification, object: nil, queue: nil, usingBlock: {(note: NSNotification) -> Void in
if weakSelf?.currentQueuePlayer.currentItem == weakSelf?.currentAudioItemOne {
weakSelf?.currentQueuePlayer.insertItem((weakSelf?.currentAudioItemTwo)!, afterItem: nil)
weakSelf?.currentAudioItemTwo.seekToTime(kCMTimeZero)
} else {
weakSelf?.currentQueuePlayer.insertItem((weakSelf?.currentAudioItemOne)!, afterItem: nil)
weakSelf?.currentAudioItemOne.seekToTime(kCMTimeZero)
}
})
Here's my code to set up the current QueuePlayer.
let audioPlayerItem = AVPlayerItem(URL: url)
currentAudioItemOne = audioPlayerItem
currentAudioItemTwo = audioPlayerItem
currentQueuePlayer = AVQueuePlayer()
currentQueuePlayer.insertItem(currentAudioItemOne, afterItem: nil)
currentQueuePlayer.play()
I've been working at this problem for several days now. Any leads or new things to try would be appreciated. The only thing I haven't tried so far is lower quality audio files. These .wav files are all over 1mb, and had be suspecting that the file size could be affecting the seamless looping.
EDIT:
Using AVPlayerLooper to create the 'Treadmill' effect:
let url = URL(fileURLWithPath: path)
let audioPlayerItem = AVPlayerItem(url: url)
currentAudioItemOne = audioPlayerItem
currentQueuePlayer = AVQueuePlayer()
currentAudioPlayerLayer = AVPlayerLayer(player: currentQueuePlayer)
currentAudioLooper = AVPlayerLooper(player: currentQueuePlayer, templateItem: currentAudioItemOne)
currentQueuePlayer.play()
EDIT 2:
afinfo on one of my wav files:
Num Tracks: 1
----
Data format: 2 ch, 44100 Hz, 'lpcm' (0x0000000C) 16-bit little-endian signed integer
no channel layout.
estimated duration: 11.302336 sec
audio bytes: 1993732
audio packets: 498433
bit rate: 1411200 bits per second
packet size upper bound: 4
maximum packet size: 4
audio data file offset: 44
not optimized
source bit depth: I16
----
You are inserting the item too late in your current solution. You need to queue up more than one initial item, so there's always a primed AVPlayerItem ready to go.
This is called the AVPlayerQueue "treadmill pattern" as better described in this WWDC 2016 session. If you're targeting iOS 10, you can use new AVPlayerLooper class which does it for you (also described in the same link). Apple has also provided a sample project which provides an example of both strategies.
Lower level solutions include queuing up the audio buffers to an AVAudioEngine instance or using an AudioQueue or mashing the buffers together yourself with an AudioUnit.
I'm developing a music instrument in iOS with two audio samples (high and low pitches) that are played with view touches. The first sample is very short (a half second) and the other is a little bigger (two seconds). When I play repeatedly and fast the low pitch sound, there is an audio click/pop. There is no problem playing the high pitch sound.
Both audio samples have fade in and fade out in their init/end and there is no clip problem with them.
I'm using this code to load the audio files (simplified here):
engine = AVAudioEngine()
mixer = engine.mainMixerNode
let player = AVAudioPlayerNode()
do {
let audioFile = try AVAudioFile(forReading: instrumentURL)
let audioFormat = audioFile.processingFormat
let audioFrameCount = UInt32(audioFile.length)
let audioFileBuffer = AVAudioPCMBuffer(PCMFormat: audioFormat, frameCapacity: audioFrameCount)
try audioFile.readIntoBuffer(audioFileBuffer)
engine.attachNode(player)
engine.connect(player, to: mixer, format: audioFileBuffer.format)
} catch {
print("Init Error!")
}
and this code to play the samples:
player.play()
player.scheduleBuffer(audioFileBuffer, atTime: nil, options: option, completionHandler: nil)
I'm using a similar functionality in Android with the same audio samples without any click/pop problem.
Is this click/pop problem an implementation error?
How can I fix this problem?
Update 1
I just tried another approach, with AVAudioPlayer and I got the same pop/click problem.
Update 2
I think the problem is to start the audio file again before its end. The sound stops abruptly.