core-audio

Can someone point me to a working version of Matt Gallagher's Tone Generator? http://www.cocoawithlove.com/assets/objc-era/ToneGenerator.zip As Matt says, it hasn't been updated and apparently got broken by newer APIs. I updated what I could figure out needed updating and now it compiles and runs with only deprecation warnings but all it does is make clicking sounds when the "Play" and "Stop" button are touched. I've gone through the code and looked at the documentation in Xcode for the API but it's a steep learning curve. I would love to have a working version so I could tinker with it to

The below code causes a crash with the following errors whenever the object is deinitialized (e.g. when performing an unwind segue back to another ViewController): required condition is false: [AVAudioEngineGraph.mm:4474:GetDefaultMusicDevice: (outputNode)] Terminating app due to uncaught exception 'com.apple.coreaudio.avfaudio', reason: 'required condition is false: outputNode' The AVAudioSequencer is the root of the issue, because the error ceases if this is removed. How can this crash be avoided? class TestAudioClass { private var audioEngine: AVAudioEngine private var sampler:

The creator of novacaine offered example code where audio data is read from a a file and fed to a ring buffer. When the file reader is created though, the output is forced to be PCM: - (id)initWithAudioFileURL:(NSURL *)urlToAudioFile samplingRate:(float)thisSamplingRate numChannels:(UInt32)thisNumChannels { ... // We're going to impose a format upon the input file // Single-channel float does the trick. _outputFormat.mSampleRate = self.samplingRate; _outputFormat.mFormatID = kAudioFormatLinearPCM; _outputFormat.mFormatFlags = kAudioFormatFlagIsFloat; _outputFormat.mBytesPerPacket = 4*self

I am trying to implement linear convolution using Core Audio, I have the algorithm implemented and working, but I am trying to write the output of this into a .wav audio file. Here is the code for the algorithm... //Create array containing output of convolution (size of array1 + array2 - 1) float *COutput; COutput = (float *)malloc(((size1+size2)-1)* sizeof(float)); int sizeOutput = ((size1 + size2)-1); //Convolution Algorithm!!! for (i=0; i<sizeOutput; i++) { COutput[i]=0; for (j=0; j<sizeCArray1; j++) { if (((i-j)+1) > 0) { COutput[i] += CArray1[i - j] * CArray2[j]; } } } I need to write the

I'm trying to sync music sent from a host iPhone to a client iPhone.. the audio is read using AVAssetReader and sent via packets to the client, which in turns feeds it to a ring buffer, which in turn populates the audioqueue buffers and starts playing. I was going over the AudioQueue docs and there seems to be two different concepts of a timestamp related to the audioQueue: Audio Queue Time and Audio Queue Device Time . I'm not sure how those two are related and when one should be used rather (or in conjunction with) the other. 来源： https://stackoverflow.com/questions/12668803/difference

I am trying to make an app that controls the volume of another process using the Windows 7 Audio API. What I'm looking for is the ISimpleAudioVolume for the session used by the other process. I have tried using the IAudioSessionEnumerator but it will only give me the IAudioSessionControl2 of the session. Using the IAudioSessionControl I have managed to receive notifications when I change the volume through sndvol but not change it myself. I have also tried using GetSimpleAudioVolume() from IAudioSessionManager but it will only give me sessions within the current process. How do you do it? It