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Questions tagged [audioqueue]

Audio Queue Services is high level. It lets your application use hardware recording and playback devices (such as microphones and loudspeakers) without knowledge of the hardware interface. It also lets you use sophisticated codecs without knowledge of how the codecs work.

At the same time, Audio Queue Services supports some advanced features. It provides fine-grained timing control to support scheduled playback and synchronization. You can use it to synchronize playback of multiple audio queues and to synchronize audio with video.

Ref Link : https://developer.apple.com/library/mac/#documentation/MusicAudio/Conceptual/AudioQueueProgrammingGuide/Introduction/Introduction.html

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Implementing and Troubleshooting Background Audio in iOS

There are a lot of questions relating to background music playback in iOS on StackOverflow. None fully explore all edge cases, the aim of this question is to be the final word in background audio question on iOS Definitions & Assumptions All…
Richard Stelling
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CoreAudio AudioQueue callback function never called, no errors reported

I am trying to do a simple playback from a file functionality and it appears that my callback function is never called. It doesn't really make sense because all of the OSStatuses come back 0 and other numbers all appear correct as well (like the…
Radiodef
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How to get array of float audio data from AudioQueueRef in iOS?

I'm working on getting audio into the iPhone in a form where I can pass it to a (C++) analysis algorithm. There are, of course, many options: the AudioQueue tutorial at trailsinthesand gets things started. The audio callback, though, gives an…
buildsucceeded
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AEC ( Echo Cancellation Support ) in OSX Using AudioQueue

I am developing VOIP Application on OSX and iOS and will be using AudioQueue for Audio flow, what want to Know is, by default does AudioQueue support acoustic echo cancellation or do we need to add support for it, If we need to implement, i believe…
Amitg2k12
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AudioSessionSetActive fails after interruption

I was trying to figure out what actually happens for weeks and I have no idea why I cannot continue playback after interruption, so probably you guys know an answer. AudioSessionSetActive(TRUE) always returns '!cat' which is…
pronebird
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Precise time of audio queue playback finish

I am using Audio Queues to playback audio files. I need precise timing on the finish of last buffer. I need to notify a function no later than 150ms-200 ms after the last buffer is played... Thru callback method I know how many buffers are…
SpaceDust__
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how to encode/decode speex with AudioQueue in ios

If anyone have some experience that encode/decode speex audio format with AudioQueue? I have tried to implement it by editing the SpeakHere sample. But not success! From the apple API document, AudioQueue can support codec, but I can't found any…
Rainbow Zhang
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Audio Queue is playing too fast when the buffer size is small

I am able to stream and play m4a files using Audio File Services + Audio Queue Services. Bitrate information of the file is not available to the Audio Queue because of file type. After downloading the all of the audio packets I feed them to the…
SpaceDust__
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Distorted (robotic) audio recording on iOS using AudioQueue

I'm using AudioQueue in iOS to implement streaming of recording to the web. The problem is that it usually works quite well, but sometimes (~20% of my attempts) the sound is horribly distorted - it sounds robotic. Edit: I am able to reproduce it…
Iftah
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Play and record audio at the same time

I need to play and record at the same time. The problem is that played and recorded sound should be different. Played sound_1 is continuously send through headphone jack to connected device, device analyzes this sound_1 and sends back another…
f3n1kc
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Best way to play a sound with an attack / sustain (loop) / decay with AVAudioPlayer

I am having a problem finding resources on playing an attack (start of sound) / sustain (looping sound) / decay (ending of sound) sequence with no transition breaks. Are there any good libraries for handling this, or should I roll my own with…
umop
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How to extract integer samples from audio queue buffer and write modified samples back?

for an iphone voice changing app (objective c), i am trying to take the sampled integer values from the recording audio queue buffer, process them in a function and write the modified values back to the play back buffer. At the moment i use…
Lukas
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How to set AudioStreamBasicDescription properties?

I'm trying to play PCM stream data from server using AudioQueue. PCM data format : Sample rate = 48000, num of channel = 2, Bit per sample = 16 And, server is not streaming fixed bytes to client. (variable bytes.) (ex : 30848, 128, 2764, ... bytes…
user6081283
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Use AudioQueue to play PCM audio stream in ios, First is ok,but no voice after 15mins

I get audio data from RTMPPacket, and I use AudioQueue to play it in IPAD. First, the voice is fine. But After about 15mins, there is no voice. Then the data is ok, and the queue is playing. I don't know why. Can anyone help me? Thanks. This is my…
chenfeng
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What exactly is an audio queue processing tap?

These have been around in OS X for a little while now and just recently became available in ios with ios 6. I am trying to figure what they let you do exactly. So the idea is you can tap into an audio queue and process the data before sending it on.…
Greg Price
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