Fix modified beam search for iOS and android (#76)

* Use Int type for sampling rate

* Fix swift

* Fix iOS

ios-swift/SherpaOnnx/SherpaOnnx/ViewController.swift

@@ -23,10 +23,10 @@ extension AVAudioPCMBuffer {
 class ViewController: UIViewController {
     @IBOutlet weak var resultLabel: UILabel!
     @IBOutlet weak var recordBtn: UIButton!
-    
+
     var audioEngine: AVAudioEngine? = nil
     var recognizer: SherpaOnnxRecognizer! = nil
-    
+
     /// It saves the decoded results so far
     var sentences: [String] = [] {
         didSet {
@@ -42,7 +42,7 @@ class ViewController: UIViewController {
         if sentences.isEmpty {
             return "0: \(lastSentence.lowercased())"
         }
-        
+
         let start = max(sentences.count - maxSentence, 0)
         if lastSentence.isEmpty {
             return sentences.enumerated().map { (index, s) in "\(index): \(s.lowercased())" }[start...]
@@ -52,23 +52,23 @@ class ViewController: UIViewController {
                 .joined(separator: "\n") + "\n\(sentences.count): \(lastSentence.lowercased())"
         }
     }
-    
+
     func updateLabel() {
         DispatchQueue.main.async {
             self.resultLabel.text = self.results
         }
     }
-    
+
     override func viewDidLoad() {
         super.viewDidLoad()
         // Do any additional setup after loading the view.
-        
+
         resultLabel.text = "ASR with Next-gen Kaldi\n\nSee https://github.com/k2-fsa/sherpa-onnx\n\nPress the Start button to run!"
         recordBtn.setTitle("Start", for: .normal)
         initRecognizer()
         initRecorder()
     }
-    
+
     @IBAction func onRecordBtnClick(_ sender: UIButton) {
         if recordBtn.currentTitle == "Start" {
             startRecorder()
@@ -78,30 +78,32 @@ class ViewController: UIViewController {
             recordBtn.setTitle("Start", for: .normal)
         }
     }
-    
+
     func initRecognizer() {
         // Please select one model that is best suitable for you.
         //
         // You can also modify Model.swift to add new pre-trained models from
         // https://k2-fsa.github.io/sherpa/ncnn/pretrained_models/index.html
-        
+
         let modelConfig = getBilingualStreamZhEnZipformer20230220()
-        
+
         let featConfig = sherpaOnnxFeatureConfig(
             sampleRate: 16000,
             featureDim: 80)
-        
+
         var config = sherpaOnnxOnlineRecognizerConfig(
             featConfig: featConfig,
             modelConfig: modelConfig,
             enableEndpoint: true,
             rule1MinTrailingSilence: 2.4,
             rule2MinTrailingSilence: 0.8,
-            rule3MinUtteranceLength: 30
+            rule3MinUtteranceLength: 30,
+            decodingMethod: "greedy_search",
+            maxActivePaths: 4
         )
         recognizer = SherpaOnnxRecognizer(config: &config)
     }
-    
+
     func initRecorder() {
         print("init recorder")
         audioEngine = AVAudioEngine()
@@ -112,9 +114,9 @@ class ViewController: UIViewController {
             commonFormat: .pcmFormatFloat32,
             sampleRate: 16000, channels: 1,
             interleaved: false)!
-        
+
         let converter = AVAudioConverter(from: inputFormat!, to: outputFormat)!
-        
+
         inputNode!.installTap(
             onBus: bus,
             bufferSize: 1024,
@@ -122,34 +124,34 @@ class ViewController: UIViewController {
         ) {
             (buffer: AVAudioPCMBuffer, when: AVAudioTime) in
             var newBufferAvailable = true
-            
+
             let inputCallback: AVAudioConverterInputBlock = {
                 inNumPackets, outStatus in
                 if newBufferAvailable {
                     outStatus.pointee = .haveData
                     newBufferAvailable = false
-                    
+
                     return buffer
                 } else {
                     outStatus.pointee = .noDataNow
                     return nil
                 }
             }
-            
+
             let convertedBuffer = AVAudioPCMBuffer(
                 pcmFormat: outputFormat,
                 frameCapacity:
                     AVAudioFrameCount(outputFormat.sampleRate)
                 * buffer.frameLength
                 / AVAudioFrameCount(buffer.format.sampleRate))!
-            
+
             var error: NSError?
             let _ = converter.convert(
                 to: convertedBuffer,
                 error: &error, withInputFrom: inputCallback)
-            
+
             // TODO(fangjun): Handle status != haveData
-            
+
             let array = convertedBuffer.array()
             if !array.isEmpty {
                 self.recognizer.acceptWaveform(samples: array)
@@ -158,13 +160,13 @@ class ViewController: UIViewController {
                 }
                 let isEndpoint = self.recognizer.isEndpoint()
                 let text = self.recognizer.getResult().text
-                
+
                 if !text.isEmpty && self.lastSentence != text {
                     self.lastSentence = text
                     self.updateLabel()
                     print(text)
                 }
-                
+
                 if isEndpoint {
                     if !text.isEmpty {
                         let tmp = self.lastSentence
@@ -175,13 +177,13 @@ class ViewController: UIViewController {
                 }
             }
         }
-        
+
     }
-    
+
     func startRecorder() {
         lastSentence = ""
         sentences = []
-        
+
         do {
             try self.audioEngine?.start()
         } catch let error as NSError {
@@ -189,7 +191,7 @@ class ViewController: UIViewController {
         }
         print("started")
     }
-    
+
     func stopRecorder() {
         audioEngine?.stop()
         print("stopped")