Add iOS support (#65)

swift-api-examples/decode-file.swift

@@ -0,0 +1,74 @@
+import AVFoundation
+
+extension AudioBuffer {
+  func array() -> [Float] {
+    return Array(UnsafeBufferPointer(self))
+  }
+}
+
+extension AVAudioPCMBuffer {
+  func array() -> [Float] {
+    return self.audioBufferList.pointee.mBuffers.array()
+  }
+}
+
+func run() {
+  let encoder = "./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/encoder-epoch-99-avg-1.onnx"
+  let decoder = "./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/decoder-epoch-99-avg-1.onnx"
+  let joiner = "./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/joiner-epoch-99-avg-1.onnx"
+  let tokens = "./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/tokens.txt"
+
+  let modelConfig = sherpaOnnxOnlineTransducerModelConfig(
+    encoder: encoder,
+    decoder: decoder,
+    joiner: joiner,
+    tokens: tokens,
+    numThreads: 2)
+
+  let featConfig = sherpaOnnxFeatureConfig(
+    sampleRate: 16000,
+    featureDim: 80
+  )
+  var config = sherpaOnnxOnlineRecognizerConfig(
+      featConfig: featConfig,
+      modelConfig: modelConfig,
+      enableEndpoint: false
+  )
+
+
+  let recognizer = SherpaOnnxRecognizer(config: &config)
+
+  let filePath = "./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/test_wavs/1.wav"
+  let fileURL: NSURL = NSURL(fileURLWithPath: filePath)
+  let audioFile = try! AVAudioFile(forReading: fileURL as URL)
+
+  let audioFormat = audioFile.processingFormat
+  assert(audioFormat.sampleRate == 16000)
+  assert(audioFormat.channelCount == 1)
+  assert(audioFormat.commonFormat == AVAudioCommonFormat.pcmFormatFloat32)
+
+  let audioFrameCount = UInt32(audioFile.length)
+  let audioFileBuffer = AVAudioPCMBuffer(pcmFormat: audioFormat, frameCapacity: audioFrameCount)
+
+  try! audioFile.read(into: audioFileBuffer!)
+  let array: [Float]! = audioFileBuffer?.array()
+  recognizer.acceptWaveform(samples: array)
+
+  let tailPadding = [Float](repeating: 0.0, count: 3200)
+  recognizer.acceptWaveform(samples: tailPadding)
+
+  recognizer.inputFinished()
+  while (recognizer.isReady()) {
+    recognizer.decode()
+  }
+
+  let result = recognizer.getResult()
+  print("\nresult is:\n\(result.text)")
+}
+
+@main
+struct App {
+  static func main() {
+    run()
+  }
+}