receive microphone sound without hearing it - actionscript

This captures microphone sound and changes the alpha of 'foo' according to the sound level. However, I hear the microphones input. I want the visuals to work without hearing any sound. How would I do that?
m = Microphone.get();
_root.attachAudio(m);
m.setVolume(0); //i can still hear sound. does not mute mic.
onEnterFrame = function () {
foo._alpha = m.activityLevel+33;
};
EDIT: ANSWER / SOLUTION
series8217's trick with setLoopBack did not work, but that led me to the answer online:
m = Microphone.get();
var myAudio:Sound=new Sound(attachAudio(m));
myAudio.setVolume(0);
thanks for your time
EDIT: OTHER SOLUTION
my trick may interfere with sound. using this, mutes the mic but flash still receives input:
m = Microphone.get();
m.setSilenceLevel(100);

Switching the loopback mode on the microphone object should do the trick.
m.setLoopBack(false);
However, if that doesn't do it, perhaps your OS sound settings have monitor or loopback mode turned on. I'd say look into that before trying setLoopback().

Related

receivedMIDIController not calling from sequencer

Current State:
I'm playing a midi file using AppleSequencer.
VirtualPorts and Listener are implemented, "receivedMIDINoteOn/Off" working great.
My Problem
"receivedMIDIController" not calling from my sequencer.
Message send from Logic Pro X's MIDI Out Port is calling "receivedMIDIController". (Same MIDI File)
I want to know what is happening, anyone can help me please?
Ok, new track with "replaceMIDINoteData" have only "modiNoteDataEvent"
var sequencer:AppleSequencer = AppleSequencer()
let t = sequencer.newTrack("track")
t?.replaceMIDINoteData(with: seqSty.tracks[0].getMIDINoteData())
//sequencer has Note Evnet Only.
a sequencer from MIDI Data has all kind of events, and then replace data with "MIDINoteData"
sequencer = AppleSequencer(fromData: data)
sequencer.tracks[0].replaceMIDINoteData(with: seqSty.tracks[0].getMIDINoteData())
//sequencer has all events from MIDI

iOS : AVFoundation - Preroll mode set during render" and my app hangs

I am developing MIDI Player by referring to the following Web-Page.
http://twocentstudios.com/2017/02/20/bouncing-midi-to-audio-on-ios/
I don't do any recording, I just want to play the SMF file.
However, when I run setPreload (true), it says "ASSERTION FAILED: Preroll mode set during render" and my app hangs.
I searched for "Preroll mode set during render" but couldn't find any valid information.
Please help someone.
EDIT:
hi, #dspr.
The percussion sounds even if I don't do "AudioUnitSetProperty (kAUMIDISynthProperty_EnablePreload: 1)".
I think this is because the BANK for percussion is automatically assigned to ch.10.
However, in this state, the piano and guitar and others do not sound.
AVAudioUnitMIDI Instrument needs kAUMIDISynthProperty_EnablePreload to analyze which tone is assigned to which track in the SMF file, right?
Which method does AVAudioUnitMIDIInstrument use to preload SMF files?
(1) AudioUnitSetProperty (kAUMIDISynthProperty_EnablePreload: 1) to AVAudioUnitMIDISynth
(2) << How to preload? >>
(3) AudioUnitSetProperty (kAUMIDISynthProperty_EnablePreload: 0) to AVAudioUnitMIDISynth
(4) Start AVAudioSequencer
MIDI Player uses the kAUMIDISynthProperty_EnablePreload property of MIDISynth for that purpose. See the Apple comment about it below. Note the It should only be used prior to MIDI playback and must be set back to 0 before attempting to start playback sentence at the end :
/*!
#constant kAUMIDISynthProperty_EnablePreload
#discussion Scope: Global
Value Type: UInt32
Access: Write
Setting this property to 1 puts the MIDISynth in a mode where it will attempt to load
instruments from the bank or file when it receives a program change message. This
is used internally by the MusicSequence. It should only be used prior to MIDI playback,
and must be set back to 0 before attempting to start playback.
*/
EDIT : frankly, I'm a little bit reserved about your link
One strategy I haven’t tried would be to pitch shift the MIDI up one octave, play it back at 2x, record it at 88.2kHz, then downsample to 44.1kHz. AVAudioSession presumably can’t go past 48kHz though.
Clearly, the person who wrote that has a very poor knowledge about audio and sampling. Playing a MIDI song transposed one octave up at double tempo is really not equivalent than playing the same recorded in audio at double speed whatever you make the recording at 88.2kHz or any other sample rate. As a simple example, what happens is the file contains a drum set ? A snare drum (40) will become a Chinese cymbal (52) played two times slower ?
As I can understand this post, the described hack has for unique purpose to make recording. So if you simply want to play your MIDI file back you can certainly find a simpler and better example.

Programmatically trigger the action that a headphone pause button would do

I am trying to find a way to pause any playing media on the device, so I was thinking of triggering the same logic that is fired when a user press the headphone "middle button"
I managed to prevent music from resuming (after I pause it within my app, which basically start an AVAudioSession for recording) by NOT setting the AVAudioSession active property to false and leave it hanging, but I am pretty sure thats a bad way to do it. If I deactivate it the music resumes. The other option I am thinking of is playing some kind of silent loop that would "imitate" the silence I need to do. But I think if what I am seeking is doable, it would be the best approach as I understood from this question it cannot be done using the normal means
func stopAudioSession() {
let audioSession = AVAudioSession.sharedInstance(
do {
if audioSession.secondaryAudioShouldBeSilencedHint{
print("someone is playing....")
}
try audioSession.setActive(false, options: .notifyOthersOnDeactivation)
isSessionActive = false
} catch let error as NSError {
print("Unable to deactivate audio session: \(error.localizedDescription)")
print("retying.......")
}
}
In this code snippet as the function name implies I set active to false, tried to find other options but I could not find another way of stopping my recording session and prevent resume of the other app that was already playing
If someone can guide me to which library I should look into, if for example I can tap into the H/W part and trigger it OR if I can find out which library is listening to this button press event and handling the pause/play functionality
A friend of mine who is more experienced in IOS development suggested the following workaround and it worked - I am posting it here as it might help someone trying to achieve a similar behaviour.
In order to stop/pause what is currently being played on a user device, you will need to add a music player into your app. then at the point where you need to pause/stop the current media, you just initiate the player, play and then pause/stop it - simple :)
like so:
let musicPlayer = MPMusicPlayerApplicationController.applicationQueuePlayer
func stopMedia(){
MPMediaLibrary.requestAuthorization({(newPermissionStatus: MPMediaLibraryAuthorizationStatus) in
self.musicPlayer.setQueue(with: .songs())
self.musicPlayer.play()
print("Stopping music player")
self.musicPlayer.pause()
print("Stopped music player")
})
}
the part with MPMediaLibrary.requestAuthorization is needed to avoid an authorisation error when accessing user's media library.
and of course you will need to add the Privacy - Media Library Usage Description
key into your Info.plist file

OnBeforePlay .seek doesn't work on iPad

I've scoured the web, upgraded the player, rewritten it 5 times, and now completing my 5th day of failing, and still cannot accomplish what the folks at Longtail tell me will work. (Don't get me wrong, I love 'em there, but this has me ready to jump off a bridge).
I'm simply trying to load a video that will play with Flash or iOS, and upon loading it, immediately go to a specific point in the video useing the .seek() method. Longtail tells me to use the onBeforePlay() function because iOS apparently doesn't respect the start value of the playlist. This code works like smoke with Flash, but ignores the seek in iOS.
Can ANYone assist me with this - it has become the most expensive script I've ever worked on and I have made zero progress at all. :( :( :( Also, I removed all the console functions and tried that, but with the same result.
Full code/player can be seen at http://www.tempurl.us/jw6e.html. You can see that with Flash, the video starts at 60 seconds, but on iOS, it starts at 0.
jwp = jwplayer('jwp').setup({
title: 'Single File Player', width: '720', height:'240', autostart: 'false', listbar: {position: "right",size: 400},
sources:[
{ file: 'http://media3.scctv.net/insight/mp4:nursing_4_clips_400.mp4/playlist.m3u8'},
{ file: 'rtmp://fms.scctv.net/insight/nursing_4_clips_400.mp4'}
]
}
);
jwp.onReady(function() {
// Create a playlist item of the video to play
var newItem = [
{ title: 'Title4 ACUTE_ABDO_PAIN_400',
image: 'playlistitem.png',
sources:[
{ file: 'http://media3.scctv.net/insight/mp4:ACUTE_ABDO_PAIN_400.mp4/playlist.m3u8'},
{ file: 'rtmp://fms.scctv.net/insight/ACUTE_ABDO_PAIN_400.mp4'}
]
}
];
jwp.load(newItem);
});
jwp.onBeforePlay(function() {
// This Works on PC/Mac with Flash, but does nothing on iPad/iPhone
jwp.seek(60);
});
Simply to close the question, the bottom line on this problem was that iOS will not allow autostart - period. Knowing that, all the expected events that were not behaving as expected made sense. Once the user initiates the stream with Play, everything works as expected. In our case, this is still a problem because we want to start later in the stream, but knowing that made dealing with it more manageable.
If the problem is iOS will not allow autostart - period. Knowing that,
all the expected events that were not behaving as expected made sense.
Once the user initiates the stream with Play, everything works as
expected
then you can have a play button only for tablet and ios device and on Clicking the play button,
call jwplayer().play(), this could be a work around for your problem, and after you have invoked jwplayer.play, which is only possible with the touch event, after play is triggeredother events will work.
otherwise even if you try jwplayer().play() onReady(), or autostart nothing will work because of iOs will not allow autostart as you said
I've solved this problem on iOS using onBeforePlay with seek() and play(). This work on desktop flash and IOS. Doesn't work on Android using the parameter androidhls:true
jwplayer().onBeforePlay(function() { jwplayer().seek(60); });
jwplayer().play();
As Ethan JWPlayer mentioned in comment use onPlay event. To prevent "loop buffering" as you said just use flag variable:
var isFirstStart = true,
seekValue = 60;
jwplayer().onPlay(function(){
//exit if it's no first playback start
if( !isFirstStart ) {
return;
}
jwplayer().seek(seekValue);
isFirstStart = false;
});

recording against a metronome of set length using remote IO

I was able to create the exact functionality I wanted to avaudioplayer and avaudiorecorder but of course experienced latency problems. So after reading pretty much every article on the web and reviewing stacks of sample code, I'm still not sure how to achieve the following:
User chooses to record a sample 2 bars long (4 beats per bar) with a pre-roll/count-in
User clicks record
A metronome starts which counts in 4 beats (accent on the first beat)
The app automatically starts recording on the start of the next bar
The app automatically turns off recording at the end of the 3rd bar (the 2 bars + the pre-roll)
The user can then playback their recording or delete it and start again.
So, with avaudioplayer and avaudiorecorder I simply created a 'caf' using audacity with a metronome set at the correct bpm (bpm is set for the app). I then setup and play the avaudioplayer and using the audiodidfinishsuccessfully delegate method, performed some logic to start the recorder, restart the player, maintain a loop count etc. to turn off recording and audio.
As I mentioned, I was pretty much able to achieve the user experience I am after but the latency problems are not acceptable.
I have been working with audio units and the remote IO and have setup a project with a playback callback and recorder callback etc. but now face the problem of working how to make this work based on the description above. I am trying to work out the following things for starters:
If I create a 1 beat caf file, how could I make use of audio units and remote IO to play x amount of beats and then stop?
How could I do the pre-roll and start the recording callback after 4 beats
Can anyone give me some ideas or point me in the right direction. As I have mentioned, I have already done a stack of research including buying the core audio book, reading every article on atastypixel.com, timbolstad.com etc and trawled through the apple docs.
Thanks in advance for your help.
I start an NSTimer. Use values based on BPM (Beats per Minute) / 60. So if user wants to record a 2 bar file with a count in might do something like this:
//timer interval=100BPM/60secs per minute
timerInterval=100/60;
metroTimer = [NSTimer scheduledTimerWithTimeInterval:timerinterval target:self selector:#selector(blinkMetroLight) userInfo:nil repeats:YES];
- (void)blinkMetroLight
{
if(beatNumber == 0)
{
beatNumber = 1;
}
else if (beatNumber == 5)
{
[self audioProcessorStart];
}
if (beatNumber == 8)
{
[self audioProcessorStop];
[metroTimer invalidate]; metroTimer = nil;
}
beatNumber++
}

Resources