I am using AVCaptureSession to develop a camera app.
I need trigger some vibration feedback when touch some UI. using code like below:
private var _impact = UIImpactFeedbackGenerator()
private var _select = UISelectionFeedbackGenerator()
private init() {
_impact.prepare()
_select.prepare()
}
func impact() {
_impact.impactOccurred()
}
func select() {
_select.selectionChanged()
}
so I can invoke select() or impact() to trigger a feedback.
But, if I add Audio Device to AVCaptureSession, all feedbacks will be invalidated. so, for the feedback effect, I have to removed AudioDevice from AVCaptureSession first, when I need to record a video, then add the Audio Device to AVCaptureSession, this operation will lag captureOutput that make camera preview freezed in little time.
So, I found another way to try this, first always add Audio Device to AVCaptureSession, then get all AVCaptureConnection about Audio from AVCaptureSession.connections. and set isEnable to false or true, But this way didn't work. even AVCaptureConnection.isEnable is false, the feedbacks also invalidate.
I think maybe there is only way to make feedback worked is don't add audio device to AVCaptureSession.
Related
I am using ReplayKit Broadcast Extension to record system screen. I am able to get the sample buffer's for video, audioApp, audioMic & process them.
Is there any way to get the microphone status i.e whether it's enabled or disabled during the screen recording?
If you have declared recorder as -
var recorder = RPScreenRecorder.shared()
Then you can check it as -
if recorder.isMicrophoneEnabled == true {
}
I am using the Player library https://github.com/piemonte/Player for video playback in my app.
I'm trying to figure out how to add the functionality to change the playback speed/rate of the video, like this: https://developer.apple.com/reference/avfoundation/avplayer/1388846-rate
I didn't see a playback function to allow this type of direct control in the Player docs.
Is there a way to change the "rate" of the underlying AVPlayer?
In this lib have the Player.swift, there you can access "_avplayer" variable that is a AVPlayer object..
You can make _avplayer public and access it from everywhere, or you can just make a getter and setter like:
open var rate: Float {
get {
return self._avplayer.rate
}
set {
self._avplayer.rate = newValue
}
}
I am testing this using iOS 10.2 on my actual iPhone 6s device.
I am playing streamed audio and am able to play/pause audio, skip tracks, etc. I also have enabled background modes and the audio plays in the background and continues through a playlist properly. The only issue I am having is getting the lock screen controls to show up. Nothing displays at all...
In viewDidLoad() of my MainViewController, right when my app launches, I call this...
func setupAudioSession(){
UIApplication.shared.beginReceivingRemoteControlEvents()
do {
try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback, with: AVAudioSessionCategoryOptions.mixWithOthers)
self.becomeFirstResponder()
do {
try AVAudioSession.sharedInstance().setActive(true)
print("AVAudioSession is Active")
} catch let error as NSError {
print(error.localizedDescription)
}
} catch let error as NSError {
print(error.localizedDescription)
}
}
and then in my AudioPlayer class after I begin playing audio I call ...
func setupLockScreen(){
let commandCenter = MPRemoteCommandCenter.shared()
commandCenter.nextTrackCommand.isEnabled = true
commandCenter.nextTrackCommand.addTarget(self, action:#selector(skipTrack))
MPNowPlayingInfoCenter.default().nowPlayingInfo = [MPMediaItemPropertyTitle: "TESTING"]
}
When I lock my iPhone and then tap the power button again to go to the lock screen, the audio controls are not displayed at all. It is as if no audio is playing, I just see my normal background photo. Also no controls are displayed in the control panel (swiping up on home screen and then swiping left to where the music controls should be).
Is the issue because I am not using AVAudioPlayer or AVPlayer? But then how does, for example, Spotify get the lock screen controls to display using their own custom audio player? Thanks for any advice / help
The issue turned out to be this line...
try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback, with: AVAudioSessionCategoryOptions.duckOthers)
Once I changed it to
try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback, with: [])
everything worked fine. So it seems that passing in any argument for AVAudioSessionCategoryPlaybackOptions causes the lock screen controls to not display. I also tried passing in .mixWithOthers an that too caused the lock screen controls to not be displayed
In Swift 4. This example is only to show the player on the lock screen and works with iOS 11. To know how to play auidio on the device you can follow this thread https://stackoverflow.com/a/47710809/1283517
import MediaPlayer
import AVFoundation
Declare player
var player : AVPlayer?
Now create a function
func setupLockScreen(){
let commandCenter = MPRemoteCommandCenter.shared()
commandCenter.nextTrackCommand.isEnabled = true
commandCenter.togglePlayPauseCommand.addTarget(self, action: #selector(controlPause))
MPNowPlayingInfoCenter.default().nowPlayingInfo = [MPMediaItemPropertyTitle: currentStation]
}
now create a function for control play and pause event. I have created a BOOL "isPlaying" to determine the status of the player.
#objc func controlPause() {
if isPlaying == true {
player?.pause()
isPlaying = false
} else {
player?.play()
isPlaying = true
}
}
And ready. Now the player will be displayed on the lock screen
Yes, for the lock screen to work you need to use iOS APIs to play audio. Not sure how Spotify does it but they may be using a second audio session in parallel for this purpose and use the controls to control both. Your background handler (the singleton in my case) could start playing the second audio with 0 volume when it goes into background and stop it when in foreground. I haven't tested it myself but an option to try.
I am doing live speech recognition with the new iOS10 framework. I use AVCaptureSession to get to audio.
I have a "listening" beep sound to notify the user he can begin talking. The best way to put that sound is at the 1st call to captureOutput(:didOutputSampleBuffer..), but if I try to play a sound after starting the session the sound just won't play. And no error is thrown.. it just silently fail to play...
What I tried:
Playing through a system sound (AudioServicesPlaySystemSound...())
Play an asset with AVPlayer
Also tried both above solutions async/sync on main queue
It seems like regardless of what I am doing, it is impossible to trigger playing any kind of audio after triggering the recognition (not sure if it's specifically the AVCaptureSession or the SFSpeechAudioBufferRecognitionRequest / SFSpeechRecognitionTask...)
Any ideas? Apple even recommends playing a "listening" sound effect (and do it themselves with Siri) but I couldn't find any reference/example showing how to actually do it... (their "SpeakToMe" example doesn't play sound)
I can play the sound before triggering the session, and it does work (when starting the session at the completion of playing the sound) but sometimes theres a lag in actually staring the recognition (mostly when using BT headphones and switching from a different AudioSession category - for which I do not have a completion event...) - because of that I need a way to play the sound when the recording actually starts, and not before it triggers and cross fingers it won't lag starting it...
Well, apparently there are a bunch of "rules" one must follow in order to successfully begin a speech recognition session and play a "listening" effect only when (after) the recognition really began.
The session setup & triggering must be called on main queue. So:
DispatchQueue.main.async {
speechRequest = SFSpeechAudioBufferRecognitionRequest()
task = recognizer.recognitionTask(with: speechRequest, delegate: self)
capture = AVCaptureSession()
//.....
shouldHandleRecordingBegan = true
capture?.startRunning()
}
The "listening" effect should be player via AVPlayer, not as a system sound.
The safest place to know we are definitely recording, is in the delegate call of AVCaptureAudioDataOutputSampleBufferDelegate, when we get our first sampleBuffer callback:
func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputSampleBuffer sampleBuffer: CMSampleBuffer!, from connection: AVCaptureConnection!) {
//only once per recognition session
if shouldHandleRecordingBegan {
shouldHandleRecordingBegan = false
player = AVPlayer(url: Bundle.main.url(forResource: "listening", withExtension: "aiff")!)
player.play()
DispatchQueue.main.async {
//call delegate/handler closure/post notification etc...
}
}
// append buffer to speech recognition
speechRequest?.appendAudioSampleBuffer(sampleBuffer)
}
End of recognition effect is hell of a lot easier:
var ended = false
if task?.state == .running || task?.state == .starting {
task?.finish() // or task?.cancel() to cancel and not get results.
ended = true
}
if true == capture?.isRunning {
capture?.stopRunning()
}
if ended {
player = AVPlayer(url: Bundle.main.url(forResource: "done", withExtension: "aiff")!)
player.play()
}
I have an app that needs to have:
Background music playing while using the app (eg. spotify)
Background music playing while watching movie from AVPlayer
Stop the music when recording a video
Like Snapchat, the camera-viewcontroller is part of a "swipeview" and therefore always on.
However, when opening and closing the app, the music makes a short "crack" noise/sound that ruins the music.
I recorded it here:
https://soundcloud.com/morten-stulen/hacky-sound-ios
(3 occurrences)
I use these settings for changing the AVAudiosession in the appdelegate didFinishLaunchingWithOptions:
do {
try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayAndRecord,withOptions:
[AVAudioSessionCategoryOptions.MixWithOthers,
AVAudioSessionCategoryOptions.DefaultToSpeaker])
try AVAudioSession.sharedInstance().setActive(true)
} catch {
print("error")
}
I use the LLSimpleCamera control for video recording and I've set the session there to:
_session.automaticallyConfiguresApplicationAudioSession = NO;
It seems others have the same problem with other camera libraries as well:
https://github.com/rFlex/SCRecorder/issues/127
https://github.com/rFlex/SCRecorder/issues/224
This guy removed the audioDeviceInput, but I kinda need that for recording video.
https://github.com/omergul123/LLSimpleCamera/issues/48
I also tried with Apple's code "AvCam", and I still have the same issue. How does Snapchat do this?!
Any help would be greatly appreciated, and I'll gladly provide more info or code!
I do something similar to what you're wanting, but without the camera aspect, but I think this will do what you want. My app allows background audio that will mix with non-fullscreen video/audio. When the user plays an audio file or a full screen video file, I stop the background audio completely.
The reason I do SoloAmbient then Playback is because I allow my audio to be played in the background when the device is locked. Going SoloAmbient will stop all background music playing and then switching to Playback lets my audio play in the app as well as in the background.
This is why you see a call to a method that sets the lock screen information in the Unload method. In this case, it is nulling it out so that there is no lock screen info.
In AppDelegate.swift
//MARK: Audio Session Mixing
func allowBackgroundAudio()
{
do {
try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback, withOptions: .MixWithOthers)
} catch {
NSLog("AVAudioSession SetCategory - Playback:MixWithOthers failed")
}
}
func preventBackgroundAudio()
{
do {
//Ask for Solo Ambient to prevent any background audio playing, then change to normal Playback so we can play while locked
try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategorySoloAmbient)
try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)
} catch {
NSLog("AVAudioSession SetCategory - SoloAmbient failed")
}
}
When I want to stop background audio, for example when playing an audio track that should be alone, I do the following:
In MyAudioPlayer.swift
func playUrl(url: NSURL?, backgroundImageUrl: NSURL?, title: String, subtitle: String)
{
ForgeHelper.appDelegate().preventBackgroundAudio()
if _mediaPlayer == nil {
self._mediaPlayer = MediaPlayer()
_mediaPlayer!.delegate = self
}
//... Code removed for brevity
}
And when I'm done with my media playing, I do this:
private func unloadMediaPlayer()
{
if _mediaPlayer != nil {
_mediaPlayer!.unload()
self._mediaPlayer = nil
}
_controlView.updateForProgress(0, duration: 0, animate: false)
ForgeHelper.appDelegate().allowBackgroundAudio()
setLockScreenInfo()
}
Hope this helps you out!