DSPGraph when Using CoreML - ios

Question

I am trying to use a SoundAnalyisis model that takes in audioSamples(Float32 15600) and returns a vggishFeature (MultiArray (Float32 12288) however I receive this error:
-01-22 10:45:43.404715+0000 SRTester[25654:891998] [DSPGraph] throwing DSPGraph::Exception with backtrace:
0 0x7fff2bdc0df9 DSPGraph::Graph::processMultiple(DSPGraph::GraphIOData*, DSPGraph::GraphIOData*) + 249
1 0x7fff2bd2223d SoundAnalysis::primeGraph(DSPGraph::Graph&, int) + 542
2 0x7fff2bcfbaae -[SNSoundClassifier primeGraph] + 134
3 0x7fff2bd052c2 -[SNAnalyzerHost primeAnalyzerGraph] + 88
4 0x7fff2bd0f268 -[SNAudioStreamAnalyzer configureAnalysisTreeWithFormat:] + 263
5 0x7fff2bd0f74b -[SNAudioStreamAnalyzer _analyzeAudioBuffer:atAudioFramePosition:] + 303
6 0x10af1cd48 _dispatch_client_callout + 8
7 0x10af2b9bf _dispatch_lane_barrier_sync_invoke_and_complete + 132
8 0x7fff2bd0f5d8 -[SNAudioStreamAnalyzer analyzeAudioBuffer:atAudioFramePosition:] + 121
9 0x10abb3116 $s8SRTester18homeViewControllerC16startAudioEngine33_CDAAA73F093090436FCAC2E152DEFC64LLyyFySo16AVAudioPCMBufferC_So0M4TimeCtcfU_yycfU_ + 326
10 0x10abb315d $sIeg_IeyB_TR + 45
11 0x10af1bdd4 _dispatch_call_block_and_release + 12
12 0x10af1cd48 _dispatch_client_callout + 8
13 0x10af235ef _dispatch_lane_serial_drain + 788
14 0x10af2417f _dispatch_lane_invoke + 422
15 0x10af2fa4e _dispatch_workloop_worker_thread + 719
[truncated?]
libc++abi.dylib: terminating with uncaught exception of type DSPGraph::Exception
(lldb)
The code throws the error in this line:
self.analyzer.analyze(buffer, atAudioFramePosition: time.sampleTime)
which belongs to this block of code:
/// Starts the audio engine
private func startAudioEngine() {
self.isLisitingForInferance = true
//requests to use the engine
do {
let request = try SNClassifySoundRequest(mlModel: soundClassifier.model)
try analyzer.add(request, withObserver: resultsObserver) // sets the results observator
} catch {
print("Unable to prepare request: \(error.localizedDescription)")
return
}
//starts a async task for the analyser
audioEngine.inputNode.installTap(onBus: 0, bufferSize: 16000, format: inputFormat) { buffer, time in
self.analysisQueue.async {
self.analyzer.analyze(buffer, atAudioFramePosition: time.sampleTime) //this line recives a SIGABRT
}
}
do{
try audioEngine.start()
}catch( _){
print("error in starting the Audio Engine")
}
}
Here is the class obsivation (although it does not even get triggered:
class ResultsObserver: NSObject, SNResultsObserving {
var delegate: iPhoneSpeakerRecongitionDelegate?
func request(_ request: SNRequest, didProduce result: SNResult) {
guard let result = result as? SNClassificationResult,
let classification = result.classifications.first else { return }
//print("here")
let confidence = classification.confidence * 100.0
//print(classification.)
if confidence > 60 {
delegate?.displayPredictionResult(identifier: classification.identifier, confidence: confidence)
}
}
}

Answer 1

Managed to get this to return a different error (which is where the model was incompatible)
To resolve this you have to manually move the model file into the app directory and then add it to xcode - it seems to be a bug in Xcode putting the model that is stored in another directory into the app package