I got a strange issue. My code works great on both iOS 5&6 but when running on iOS 7 I get empty buffers on the AudioQueue callback.
Possible relevant code:
- (void)setUpAudioFormat
{
audioFormat.mFormatID = kAudioFormatLinearPCM;
audioFormat.mSampleRate = SAMPLE_RATE;//16000.0;
audioFormat.mChannelsPerFrame = CHANNELS;//1;
audioFormat.mBitsPerChannel = 16;
audioFormat.mFramesPerPacket = 1;
audioFormat.mBytesPerFrame = audioFormat.mChannelsPerFrame * sizeof(SInt16);
audioFormat.mBytesPerPacket = audioFormat.mBytesPerFrame * audioFormat.mFramesPerPacket;
audioFormat.mFormatFlags = kLinearPCMFormatFlagIsSignedInteger
| kLinearPCMFormatFlagIsPacked;
bufferNumPackets = 2048; // must be power of 2 for FFT!
bufferByteSize = [self byteSizeForNumPackets:bufferNumPackets];
}
- (UInt32)numPacketsForTime:(Float64)seconds
{
return (UInt32) (seconds * audioFormat.mSampleRate / audioFormat.mFramesPerPacket);
}
- (UInt32)byteSizeForNumPackets:(UInt32)numPackets
{
return numPackets * audioFormat.mBytesPerPacket;
}
- (void)setUpRecordQueue
{
NSLog(@"\n+++ setUpRecordQueue");
OSStatus errorStatus = AudioQueueNewInput(
&audioFormat,
recordCallback,
self, // userData
CFRunLoopGetMain(), // run loop
NULL, // run loop mode
0, // flags
&recordQueue);
if (errorStatus) {
NSLog(@"\n\n ERROR : Error %ld on AudioQueueNewInput\n", errorStatus );
}
if (recordQueue == nil) {
NSLog(@"\n\n ----- Record Queue is nil! -----");
}
UInt32 trueValue = true;
AudioQueueSetProperty(recordQueue,kAudioQueueProperty_EnableLevelMetering,&trueValue,sizeof (UInt32));
}
- (void)setUpRecordQueueBuffers
{
NSLog(@"\n+++ setUpRecordQueueBuffers");
assert(recordQueue != nil);
for (int t = 0; t < NUMBER_AUDIO_DATA_BUFFERS; ++t)
{
OSStatus errorStatus = AudioQueueAllocateBuffer(
recordQueue,
bufferByteSize,
&recordQueueBuffers[t]);
if (errorStatus) {
NSLog(@"\n\n ERROR : Error %ld on AudioQueueAllocateBuffer\n", errorStatus );
}
}
}
- (void)primeRecordQueueBuffers
{
NSLog(@"\n+++ primeRecordQueueBuffers");
assert(recordQueue != nil);
for (int t = 0; t < NUMBER_AUDIO_DATA_BUFFERS; ++t)
{
OSStatus errorStatus = AudioQueueEnqueueBuffer(
recordQueue,
recordQueueBuffers[t],
0,
NULL);
if (errorStatus) {
NSLog(@"\n\n ERROR : Error %ld on AudioQueueEnqueueBuffer\n", errorStatus );
}
}
}
- (void)startRecording
{
[self startRecording:FALSE];
}
- (void)startRecording:(BOOL) autoStop
{
NSLog(@"Starting to record");
recording = YES;
shouldStopRecording = NO;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)
, ^{
NSLog(@"PPPP C1");
_frameIndex= 0;
self.fileWasCreated = NO;
[self setUpRecordQueue];
NSLog(@"PPPP C2");
[self setUpRecordQueueBuffers];
NSLog(@"PPPP C3");
[self primeRecordQueueBuffers];
NSLog(@"PPPP C4");
AudioQueueStart(recordQueue, NULL);
NSLog(@"PPPP C5");
if (autoStop) {
[self stopRecording];
}
});
}
- (void)stopRecording
{
NSLog(@"Stoping to record");
if (recordQueue != nil) {
NSString *osVersion = [[UIDevice currentDevice] systemVersion];
if ([osVersion doubleValue]<6){
AudioQueueDispose(recordQueue, TRUE);
}
else {
AudioQueueStop(recordQueue, FALSE);
}
recordQueue = nil;
}
NSLog(@"Stopped recording");
shouldStopRecording = YES;
recording = NO;
}
The Callback:
static void recordCallback(
void* inUserData,
AudioQueueRef inAudioQueue,
AudioQueueBufferRef inBuffer,
const AudioTimeStamp* inStartTime,
UInt32 inNumPackets,
const AudioStreamPacketDescription* inPacketDesc)
{
NSLog(@"recordCallback %u", (unsigned int)inBuffer->mAudioDataByteSize);
// I get always zero here...
}
Btw, The mic permission is ok (enable access to mic).
UPDATE: Seems like the AudioQueueStart failed with error -50. This happens on iOS 7 only. Is there any issue with parameters I've set?
I found the issue! seems like on iOS 7 there is a need to set this also (I assume this is only practically therefore it's hard to find, isn't written anywhere). Just add this code before calling any AudioQueue function:
AudioSessionInitialize(NULL,
NULL,
nil,
( void *)(self)
);
UInt32 sessionCategory = kAudioSessionCategory_PlayAndRecord;
AudioSessionSetProperty(kAudioSessionProperty_AudioCategory,
sizeof(sessionCategory),
&sessionCategory
);
AudioSessionSetActive(true);
Hope that would help others.
Another resource that can help can be found here.
@Idan your answer is correct and working but it only shows warning if app minimun deployment target is iOS 7. For iOS 7 we can do something like this:
NSError *audioSessionError;
AVAudioSession *audioSession = [AVAudioSession sharedInstance];
[audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:&audioSessionError];
if(audioSessionError)
{
NSLog(@"AVAudioSession error setting category:%@",audioSessionError);
}
else
{
[audioSession setActive:YES error:&audioSessionError];
if(audioSessionError)
NSLog(@"AVAudioSession error activating: %@",audioSessionError);
}
来源:https://stackoverflow.com/questions/18959554/audioqueue-callback-get-empty-buffer-on-ios-7-only