I have large looping background music files of up to 10 minutes length. The sounds are looped perfectly and if the player introduces no delay you would not notice where the loop point is.
Can AVAudioPlayer play them without that the user will hear a gap caused by latency or other problems with looping?
You might be hearing a delay because your music is compressed (mp3 for example). AVAudioPlayer has to decode the mp3 as it streams. If you had the same music in an uncompressed format, it would take significantly more disk space, but would loop seamlessly.
As long as you don't stop/start it at the end and you set numberOfLoops to a negative integer, it should work.
I had problems trying to create seamless loops. I tried using the numberOfLoops property, with no success. I tried switching to uncompressed audio files, with no success. I even tried switching to an AVAudioQueuePlayer, queued with multiple instances of the same asset, with no success. In the end I solved the problem by creating two instances of AVAudioPlayer (player1 & player2) and switching between them. I began playback of player1 and used player2's prepareToPlay method, and the play(atTime time:) method setting the TimeInterval to player1.deviceCurrentTime - player1.currentTime + player1.duration.
I then used the delegate method audioPlayerDidFinishPlaying to prepare player1 to restart playback after player2 was done. To be honest, I don't know why this approach worked and simply setting numberOfLoops to -1 did not. But it may work for you also
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I am making a music game and when the user presses a note it will produce a sound. The sound naturally needs to play immediately when the user presses, so they can tell whether they are in time with the music. However, it feels as if the sound is lagging, especially when note presses become quicker.
My background .m4a music file is played with AVAudioPlayer. I chose to use this over Cocos Denshion as I have access to the currentTime property. I may be wrong, but I dont think I can access this with CocosDenshion.
I made a .wav file which is extremely short (less than a second). I preload my sound effect on init:
[[SimpleAudioEngine sharedEngine] preloadEffect:#"Assist.wav"];
Then to play the sound effect, in CCTouchesBegan I call:
[[SimpleAudioEngine sharedEngine] playEffect:#"Assist.wav"];
After that it calls my code to determine the users timing and awards points. Any idea why it might be lagging, or a better way to play sound effects in time with music?
EDIT: Ive tried a few things recently with no results. First I tried playing the sounds automatically as they came up to the appropriate time in the song. Still had the lag, so I dont think it is touch events being slow. I also tried 3 different sound libraries.
However, when I ran in the simulator, it seemed to not be laggy. Does anyone have an idea? Im clueless and its a major feature I cant really take out...
you should avoid this code:- [[SimpleAudioEngine sharedEngine] preloadEffect:#"Assist.wav"];
with the start of app you should load your framework SimpleAudioEngine by writing this code :-
//SimpleAudioEngine *palySound; made object in .h file.
palySound=[SimpleAudioEngine sharedEngine];
and whenever you want to play sound you can write: [palySound playEffect:#"Assist.wav"];
I am not sure what you're doing in your SoundEngine, but in my own experience, the best way to not get lag to play a sound is to assign an AVAudioPlayer for each sound file (unless you want to start messing around with AudioQueues).
Here it is an example:
Let's assume that you have an AVAudioPlayer *assistPlayer; in your current view controller.
In your viewDidLoad initialize it with your sound:
NSURL *wavURL = [[NSBundle mainBundle] URLForResource:#"Assist" withExtension:#"wav"];
assistPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:wavURL error:nil];
Then, in your IBAction where you want to play the file, just do:
[assistPlayer play];
You shouldn't get any lag.
Did you try Finch? It claims to play sounds with low latency, and it is also just a wrapper around OpenAL.
Other than that, I'm really not experienced with OpenAL, but can think of two possible reasons for your lag:
The main thread is too busy - Try to offload work from it to other
threads.
Perhaps OpenAL is defined with too large of a buffer, so the pipeline loads the entire sound into the buffer (or a big chunk of it), and only afterwards the playback starts.
I am developing a game for the iPhone and iPad using cocos2d, and I need to be able to play a sound exactly when another one completes.
I have a soundtrack that is chopped up in smaller pieces, and there are no room for the tinyest gap between playback when one finishes and one starts.
Btw. I cannot glue the sounds together into a single file and just play that since the order of the files will be rearranged runtime.
How can I achieve this?
With CocosDenshion you can register a delegate with
[[CDAudioManager sharedManager] setBackgroundMusicCompletionListener:self
selector:#selector(musicDidFinish)];
CDAudioManager class reference
This delegate will be called whenever the background music ends. This of course only works if you play your sound files as background music (with the playBackgroundMusic method).
If that doesn't work for you, have a look at ObjectAL. You'll have more options and greater flexibility. For example, with ALSource you can queue multiple ALBuffer objects which represent sound files. That means whenever the source's buffer count decreases to 1 you just queue the next buffer to achieve uninterrupted, sequential playback of multiple sound files (any format).
Because ObjectAL is so awesome (well, I think so :) ) it's included and ready to use in Kobold2D.
You can use a single Audio Queue or the RemoteIO Audio Unit, and just fill the callback buffers with raw/PCM audio samples from any file in any order.
I need to play sounds (~5 seconds each) throughout my iphone application. When they're triggered, they need to play immediately.
For the moment I'm using AudioServices and (as you probably know) the first time you play a sound it lags, then every time there after it's perfect. Is there some code available that's clever enough to preload an AudioServices sound (by playing it silently maybe?). I've read adjusting the system volume programmatically will get your app rejected, so that's not an option. Seems AudioServices isn't made for volume correction from what I can see.
I've looked into OpenAL and while feasible seems a little over kill. AVAudioPlayer seems like a little bit of a better option, I'm using that for background music at present. Extending my music player to handle a 'sound board' might be my last resort.
On the topic of OpenAL, does anyone know of a place with a decent (app store friendly) OpenAL wrapper for the iPhone?
Thanks in advance
Finch could be perfect for you. It’s a tiny wrapper around OpenAL with very low latency and simple API. See also all SO questions tagged ‘Finch’.
If you use an AVAudioPlayer, you can call prepareToPlay when you initialize the object to reduce the delay between calling play and having the audio start.
I am using Stephen Celis' SCListener class to record iPhone microphone audio levels. I also am playing audio through the use of AVAudioPlayer. For example, the user presses 'Play' to kick off a sound playing in the background and then has the option to blow into the microphone to play additional, shorter sounds. The code all works fine, playing all the sounds when they should be played, however, the AVAudioPlayer sound volume greatly decreases when you begin listening with the SCListener. I have narrowed down the culprit to this line in the SCListener source code:
AudioQueueNewInput(&format, listeningCallback, self, NULL, NULL, 0, &queue);
I have racked my brain and can not find out how to keep the playback volume at it's highest level once this line has executed. I have spoken with Stephen Celis, too, and he does not know what is happening. It is possible, I suppose, that the iPhone turns down the output volume when the microphone is being used so that feedback isn't introduced, but it seems like there should be a way to disable that.
In summary:
Start playing long audio file with AVAudioPlayer - 100% volume (loud).
Enable SCListener and begin listening (which calls AudioQueueNewInput).
The output volume on the AVAudioPlayer sound greatly decreases
Call [[SCListener sharedListener] stop] to dispose of the queue
AVAudioPlayer sound resumes higher playback volume
Has anyone seen anything like this or have any ideas on how to keep the playback volume higher? I have explicitly set the volume parameter to 1.0f to ensure that the gain is at it's highest level.
you can try this:
UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,sizeof (audioRouteOverride),&audioRouteOverride);
I'm not familiar with Stephen Celis's work, but if tposchel's suggestion does not work, it might be of some value to look at the InputQueue's values versus the OutputQueue's audio values in debug mode (this is tricky, though, since the callbacks for these methods are realtime threads).
This may be informative in that it will tell you what the OS believes it is sending to your output device (headphone, or built-in speaker).
The brute force way to fix this problem is to manually normalize (or scale up, as it were) the values within your OutputQueue's callback. This doesn't address your root problem, perhaps, but may be a hack until you find the answer.
I am trying to develop a simple iPhone app. I need to play sound within a loop.
How can Play Audio file in loop without any interruption ?
Take a look at the new AVAudioPlayer class in the 2.2 release:
http://developer.apple.com/iphone/library/documentation/AVFoundation/Reference/AVAudioPlayerClassReference/Reference/Reference.html
It has functionality for looping sounds.
I really don't know the iPhone SDK at all, but this should be quick: try making the sound itself looping. That way, you should be able to play it with just a single call, and won't need to worry about timing the repeat properly to restart it at the exact right moment.
For instance, WAV files have very flexible support for looping, and any decent audio editor should let you set looping points.
The AVAudioPlayer has numberOfLoops property where you can specify the number of times you want the audio to loop.