HI, i'm trying to create a repeating dtmf tone so i can play it with AVAudioPlayer. Currently when i loop it in some audio editing software such as audacity there is always a glitch or change in tone at the point where it repeats. Is there some particular length of time i need to create it to avoid this. I initally created a one second ...
I'm playing an audio clip using a UIButton that calls a method (see code below). I'm trying to figure out how to write a statement to detect if the audio is running, and if the audio file is playing then disable/hide the UIButton. At the moment if you keep touching the play button multiple instances of the audio clip play. -(void) aud...
I have the following code to send as audio RTP packet some DTMF digits: int count=0 for(int j = 0; j < samples; j++) { waves = 0; // dtmf tone 1 waves += sin( ((PI * 2.0f / 8000) * 697.0f) * count ); waves += sin( ((PI * 2.0f / 8000) * 1209.0f) * count); waves *= 8191.0f; //amplitude ++coun...
Hi all, I want to be notified if headphones are plugged in or plugged out. I'm currently doing this using a property listener like this: AudioSessionAddPropertyListener (kAudioSessionProperty_AudioRouteChange, myCallback, self); This works perfectly well in all cases except in one, it goes like this: Launch, iPhone is unmuted, no he...
Hello. My game has 3 background songs. I would like the game to set the background music to off when there is ipod music playing, else it will play the last played piece of music. When the muser changes the music with the ipod music on, the ipod music should go away and the background music plays. The problem is, the second time I try t...
Hi everyone, I am developing an iOS application (targetted specifically for iPhone, at the moment) that requires the application to record audio only from iPhone internal microphone (even when headphone/headset is plugged in), and playback at headphone (let's assumed headphone is plugged in for now). I am wondering if this is currently...
Hi I have an iPhone application which requires me to play a looping mp3 sound during the entire lifetime of app. But based on some actions performed by user this mp3 should stop/pause for while & another mp3 should play & then this mp3 should resume playing again. I havent really used any audio API on iPhone yet, I've just used Audio...
Could someone explain to me how OpenAL fits in with the schema of sound on the iPhone? There seem to be APIs at different levels for handling sound. The higher level ones are easy enough to understand. But my understanding gets murky towards the bottom. There is Core Audio, Audio Units, OpenAL. What is the connection between these? ...
I record audio in .caf format and later need to convert it to .wav in order to send the file as a email attachment. How can I convert the file to wav format in iOS 3.1.x? The format of the audio: [NSNumber numberWithInt:kAudioFormatLinearPCM], AVFormatIDKey, [NSNumber numberWithFloat:11025.0f], AVSampleRateKey, [NSNumber nu...
I would like to use the Core Audio extended audio file services framework to read a mp3 file, process it as a PCM, then write the modified file back as a mp3 file. I am able to convert the mp3 file to PCM, but am NOT able to write the PCM file back as a mp3. I have followed and analyzed the Apple ExtAudioFileConvertTest sample and also...
Hi, does anyone know how to make a simple EQ audio unit (3 bands - low, mid, hi) with iOS ? I know how to add an iPod EQ Audio Unit to my AU Graph. But it only give you access to presets and I need proper control of the EQ. I've looked around for some tutorials or explanations but no luck. Thanks. André ...
When to set kAudioUnitProperty_StreamFormat (and kAudioUnitProperty_SampleRate too)? For each AU in my AUGraph ? Or is it enough to set it jus for the AU Mixer ? André ...
What is the difference between CAStreamBasicDescription and AudioStreamBasicDescription? Thanks. ...
Hi, I have a button that triggers a sound on an iphone. I am using AudioUnits to minimize the latency. Right now, if the user taps the button twice, the sound do not overlap and the first triggered sound is cut by the second sound. Is there an easy way to let the (same) sound overlapping as many times as the user taps the buttons? Tha...
I am using code like this: CFURLRef fileURL = [self allocFullFileURL]; NSError err; [audioPlayer release]; audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:(NSURL)fileURL error:&err]; [audioPlayer prepareToPlay]; audioPlayer.delegate = self; [audioPlayer play]; CFRelease(fileURL); to play a file on an iphon...
I am trying to do what I naively thought was the simple task of trimming off the front and back of some audio my app records from the mic. Right now I have a PCM audio in a .caf file that I need to trim from some timeindex to some timeindex. I have discovered ExtAudioFile... methods that seem to do what I want, albeit criptically. There...
I am trying to extract level data from a PCM audio file using core audio. I have gotten as far as (I believe) getting the raw data into a byte array (UInt8) but it is 16 bit PCM data and I am having trouble reading the data out. The input is from the iPhone microphone, which I have set as: [recordSetting setValue:[NSNumber numberWithInt...