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.
Related
I'd like to play multiple sound sequentially.
The sound data will be available via NSData.
(to be more precise, I'm going to play different sound whenever scrollViewDidEndScrolling is called, and stop previous sound if it is still playing)
Do I need to alloc/init AVAudioPlayer for every sequential sound?
If alloc/init/release AVAudioPlayer isn't a big deal, I could do that but I'm not sure
If using the higher-level AVAudioPlayer, then yes, you'd need to instantiate (alloc/init) an AVAudioPlayer for each.
Yet, the "expensive" part (time-wise) is prepareToPlay - which you could call in a separate thread, thus hopefully by the time you come to play any given sound, it will be fully ready to play.
I am sure there is a way to do this, and I don't know how, and am new to sound in Cocos2d. I am using SimpleAudioEngine.h as directed to in Ray Wenderlich's wonderful tutorial (Part 1). The problem is, there is a delay when it plays a sound. I KNOW for a fact that there is a way to get rid of the delay, because, just look at all the games that are already out for iPhone!! Note that I am doing this on the Simulator, not on a real device, if that makes a difference. Any help is appreciated. Thanks!!
Have you tried preloadEffect? preload audio effects at initialize before calling playEffect:.
[[SimpleAudioEngine sharedEngine] preloadEffect:#"pew-pew-lei.caf"];
This fix might not work. If the sound engine is not initialized properly, it will never preload properly.
Another possibility of sound stuttering: your code might be asking for multiple resource files at the same time, and if you are not multi-threading, it can affect the sound effects.
To test for this: comment out your code when the sound effects play. If the sound effects do not stutter with your code commented out, that means your code is 'keeping the device or thread busy'.
I found this issue when I played an explosion animation. When I commented out the animation code, the sound effect did not stutter the game play.
I have set up an AVAudioPlayer object in viewDidLoad, as per the Apple guidelines, calling prepareToPlay as the last line in viewDidLoad (i have tried in awakeFromNib also).
When i press my play button, there is a pause, as it would appear to load the file, then it plays.
In audioPlayerDidFinishPlaying, i reload the player with a different sound, and when clicking play for a second time, the file plays instantly.
What would cause the player to lag on the first play?
Thanks.
The delay is due to AVAudioPlayer being initialised. Please see this answer.
The audio system runs on several asynchronous software processes (audio units, OS drivers, etc.) and hardware systems (DMA, DACs, audio amp power supplies, etc.) that never really all completely finish initialization until some sound is actually played all the way out the speakers or earphones.
Here's one method to do that: Create a sound file containing a half second of silence. On app start up, while your app and view controller are still loading, use AVAudioPlayer to play this file of silence. Now when your view finishes loading, AVAudioPlayer should be ready to play subsequent non-silent sounds much faster, since some audio (silence) has already already gone all the way out to the speakers.
What kind of sound are you playing? Alerts, something longer? If alerts, I did go this way and it's much better with lags ...
create system sound with AudioServicesCreateSystemSoundID
play system sound with AudioServicesPlaySystemSound
dispose system sound with AudioServicesDisposeSystemSoundID
... you only need to store SystemSoundID for each sound you would like to play.
I have a few single hit sounds(small sound effects) which I want to play when a button is pressed. Should I declare the player and then initialize the sound to the player in the IBAction of the button if I want to play different sounds on different buttons?
Or is there a method to call which you specify the sound as you play it?
the [audioPlayer play] statement plays what is already initialized or added to the player. How can I setup the play and call it at different places with some predefined sound?
Thanks
There's a bit of delay whenever you start playing a sound even if it's already loaded and all you have to do is hit [audioPlayer play]
If you need to initialize it before you play it i'd imagine the delay would be much more noticeable.
I think i'd make a separate audio player for each sound and populate an array with them. Keep an eye out for memory low messages and unload the objects if necessary but i don't think it will require much overhead.
I have a performance-intensive iPhone game I would like to add sounds to. There seem to be about three main choices: (1) AVAudioPlayer, (2) Audio Queues and (3) OpenAL. I’d hate to write pages of low-level code just to play a sample, so that I would like to use AVAudioPlayer. The problem is that it seems to kill the performace – I’ve done a simple measuring using CFAbsoluteTimeGetCurrent and the play message seems to take somewhere from 9 to 30 ms to finish. That’s quite miserable, considering that 25 ms == 40 fps.
Of course there is the prepareToPlay method that should speed things up. That’s why I wrote a simple class that keeps several AVAudioPlayers at its disposal, prepares them beforehand and then plays the sample using the prepared player. No cigar, still it takes the ~20 ms I mentioned above.
Such performance is unusable for games, so what do you use to play sounds with a decent performance on iPhone? Am I doing something wrong with the AVAudioPlayer? Do you play sounds with Audio Queues? (I’ve written something akin to AVAudioPlayer before 2.2 came out and I would love to spare that experience.) Do you use OpenAL? If yes, is there a simple way to play sounds with OpenAL, or do you have to write pages of code?
Update: Yes, playing sounds with OpenAL is fairly simple.
AVAudioPlayer is very marginal for game audio. Tackling AudioQueue or OpenAL by adapting one of the examples is definitely the way to go. latency is much more controllable that way.
If you're calling play on the main thread, try running it on a separate thread. What I ended up doing is:
#include <dispatch/dispatch.h>
dispatch_queue_t playQueue = dispatch_queue_create("com.example.playqueue", NULL);
AVAudioPlayer* player = ...
dispatch_async(playQueue, ^{
[player play];
});
which fixed the worst of the framerate stuttering I was experiencing.
I use OpenAL and the classes that came with the CrashLanding sample code. It's worked fine so far to play samples and play looped music all at the same time. I'm currently learning how to release the memory I've allocated for a sound (.wav file) when, for example, I want to play some intro music just once.
Use CocosDenshion – it’s free, easy, and works. It wraps AVAudioPlayer for background tracks and OpenAL for sounds.
Do you want to check the buffering with the implementation you're using? It might be somehow related to the 20ms delay you're experiencing. i.e., try to play around with the buffer size.