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avfoundation cmsamplebufferref ios objective-c swift

Deep Copy of Audio CMSampleBuffer

I am trying to create a copy of a CMSampleBuffer as returned by captureOutput in a AVCaptureAudioDataOutputSampleBufferDelegate.

The problem I am having is that my frames coming from delegate method captureOutput:didOutputSampleBuffer:fromConnection: being dropped after I retain them in CFArray for long time.

Obviously, I need to create deep copies of incoming buffers for further processing. I also know that CMSampleBufferCreateCopy only creates shallow copies.

There are few related questions were asked on SO:

But none of them helps me to use correctly CMSampleBufferCreate function with 12 parameters:

  CMSampleBufferRef copyBuffer;
CMBlockBufferRef data = CMSampleBufferGetDataBuffer(sampleBuffer);
CMFormatDescriptionRef formatDescription = CMSampleBufferGetFormatDescription(sampleBuffer);
CMItemCount itemCount = CMSampleBufferGetNumSamples(sampleBuffer);
CMTime duration = CMSampleBufferGetDuration(sampleBuffer);
CMTime presentationStamp = CMSampleBufferGetPresentationTimeStamp(sampleBuffer);
CMSampleTimingInfo timingInfo;
timingInfo.duration = duration;
timingInfo.presentationTimeStamp = presentationStamp;
timingInfo.decodeTimeStamp = CMSampleBufferGetDecodeTimeStamp(sampleBuffer);
size_t sampleSize = CMBlockBufferGetDataLength(data);
CMBlockBufferRef sampleData;
if (CMBlockBufferCopyDataBytes(data, 0, sampleSize, &sampleData) != kCMBlockBufferNoErr) {
VLog(@"error during copying sample buffer");
}
// Here I tried data and sampleData CMBlockBuffer instance, but no success
OSStatus status = CMSampleBufferCreate(kCFAllocatorDefault, data, isDataReady, nil, nil, formatDescription, itemCount, 1, &timingInfo, 1, &sampleSize, &copyBuffer);
if (!self.sampleBufferArray) {
self.sampleBufferArray = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
//EXC_BAD_ACCESS crash when trying to add sampleBuffer to the array
CFArrayAppendValue(self.sampleBufferArray, copyBuffer);
} else {
CFArrayAppendValue(self.sampleBufferArray, copyBuffer);
}

How do you deep copy Audio CMSampleBuffer? Feel free to use any language (swift/objective-c) in your answers.