Wrap VAD APIs to C# (#946)

@@ -2,7 +2,10 @@
 
 cd dotnet-examples/
 
-cd offline-punctuation
+cd vad-non-streaming-asr-paraformer
+./run.sh
+
+cd ../offline-punctuation
 ./run.sh
 
 cd ../speaker-identification

@@ -67,7 +67,7 @@ jobs:
             -DCMAKE_BUILD_TYPE=Release \
             -DSHERPA_ONNX_ENABLE_WEBSOCKET=OFF \
             -DBUILD_ESPEAK_NG_EXE=OFF \
-            -DSHERPA_ONNX_ENABLE_BINARY=OFF \
+            -DSHERPA_ONNX_ENABLE_BINARY=ON \
             ..
 
           cmake --build . --target install --config Release
@@ -197,6 +197,7 @@ jobs:
           cp -v scripts/dotnet/examples/streaming-hlg-decoding.csproj dotnet-examples/streaming-hlg-decoding
           cp -v scripts/dotnet/examples/speaker-identification.csproj dotnet-examples/speaker-identification
           cp -v scripts/dotnet/examples/offline-punctuation.csproj dotnet-examples/offline-punctuation
+          cp -v scripts/dotnet/examples/vad-non-streaming-asr-paraformer.csproj dotnet-examples/vad-non-streaming-asr-paraformer
 
           ls -lh /tmp
 

@@ -17,7 +17,6 @@ using System;
 
 class OfflinePunctuationDemo
 {
-
   static void Main(string[] args)
   {
     var config = new OfflinePunctuationConfig();
@@ -42,4 +41,3 @@ class OfflinePunctuationDemo
     }
   }
 }
-

@@ -21,6 +21,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "speaker-identification", "s
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "offline-punctuation", "offline-punctuation\offline-punctuation.csproj", "{42D85582-BB63-4259-A4EA-837D66AC078B}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "vad-non-streaming-asr-paraformer", "vad-non-streaming-asr-paraformer\vad-non-streaming-asr-paraformer.csproj", "{8CD6B7E5-F59F-47B3-BB87-2B2E3678924D}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -66,5 +68,9 @@ Global
 		{42D85582-BB63-4259-A4EA-837D66AC078B}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{42D85582-BB63-4259-A4EA-837D66AC078B}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{42D85582-BB63-4259-A4EA-837D66AC078B}.Release|Any CPU.Build.0 = Release|Any CPU
+		{8CD6B7E5-F59F-47B3-BB87-2B2E3678924D}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{8CD6B7E5-F59F-47B3-BB87-2B2E3678924D}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{8CD6B7E5-F59F-47B3-BB87-2B2E3678924D}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{8CD6B7E5-F59F-47B3-BB87-2B2E3678924D}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 EndGlobal

+// Copyright (c)  2024  Xiaomi Corporation
+//
+// This file shows how to use a silero_vad model with a non-streaming Paraformer
+// for speech recognition.
+using SherpaOnnx;
+using System.Collections.Generic;
+using System;
+
+class VadNonStreamingAsrParaformer
+{
+  static void Main(string[] args)
+  {
+    // please download model files from
+    // https://github.com/k2-fsa/sherpa-onnx/releases/tag/asr-models
+    OfflineRecognizerConfig config = new OfflineRecognizerConfig();
+    config.ModelConfig.Paraformer.Model = "./sherpa-onnx-paraformer-zh-2023-03-28/model.int8.onnx";
+    config.ModelConfig.Tokens = "./sherpa-onnx-paraformer-zh-2023-03-28/tokens.txt";
+    config.ModelConfig.Debug = 0;
+    OfflineRecognizer recognizer = new OfflineRecognizer(config);
+
+    VadModelConfig vadModelConfig = new VadModelConfig();
+    vadModelConfig.SileroVad.Model = "./silero_vad.onnx";
+    vadModelConfig.Debug = 0;
+
+    VoiceActivityDetector vad = new VoiceActivityDetector(vadModelConfig, 60);
+
+    string testWaveFilename = "./lei-jun-test.wav";
+    WaveReader reader = new WaveReader(testWaveFilename);
+
+    int numSamples = reader.Samples.Length;
+    int windowSize = vadModelConfig.SileroVad.WindowSize;
+    int sampleRate = vadModelConfig.SampleRate;
+    int numIter = numSamples / windowSize;
+
+    for (int i = 0; i != numIter; ++i) {
+      int start = i * windowSize;
+      float[] samples = new float[windowSize];
+      Array.Copy(reader.Samples, start, samples, 0, windowSize);
+      vad.AcceptWaveform(samples);
+      if (vad.IsSpeechDetected()) {
+        while (!vad.IsEmpty()) {
+          SpeechSegment segment = vad.Front();
+          float startTime = segment.Start / (float)sampleRate;
+          float duration = segment.Samples.Length / (float)sampleRate;
+
+          OfflineStream stream = recognizer.CreateStream();
+          stream.AcceptWaveform(sampleRate, segment.Samples);
+          recognizer.Decode(stream);
+          String text = stream.Result.Text;
+
+          if (!String.IsNullOrEmpty(text)) {
+            Console.WriteLine("{0}--{1}: {2}", String.Format("{0:0.00}", startTime),
+                String.Format("{0:0.00}", startTime+duration), text);
+          }
+
+          vad.Pop();
+        }
+      }
+    }
+  }
+}
+

+../online-decode-files/WaveReader.cs
\ No newline at end of file

+#!/usr/bin/env bash
+
+set -ex
+
+if [ ! -f ./silero_vad.onnx ]; then
+  curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/silero_vad.onnx
+fi
+
+if [ ! -f ./lei-jun-test.wav ]; then
+  curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/lei-jun-test.wav
+fi
+
+if [ ! -f ./sherpa-onnx-paraformer-zh-2023-03-28/tokens.txt ]; then
+  curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-paraformer-zh-2023-03-28.tar.bz2
+
+  tar xvf sherpa-onnx-paraformer-zh-2023-03-28.tar.bz2
+  rm sherpa-onnx-paraformer-zh-2023-03-28.tar.bz2
+fi
+
+dotnet run

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <RootNamespace>vad_non_streaming_asr_paraformer</RootNamespace>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="org.k2fsa.sherpa.onnx" Version="*" />
+  </ItemGroup>
+
+</Project>

@@ -39,10 +39,6 @@ public class VadNonStreamingParaformer {
     String model = "./sherpa-onnx-paraformer-zh-2023-03-28/model.int8.onnx";
     String tokens = "./sherpa-onnx-paraformer-zh-2023-03-28/tokens.txt";
 
-    String waveFilename = "./sherpa-onnx-paraformer-zh-2023-03-28/test_wavs/3-sichuan.wav";
-
-    WaveReader reader = new WaveReader(waveFilename);
-
     OfflineParaformerModelConfig paraformer =
         OfflineParaformerModelConfig.builder().setModel(model).build();
 

+/// Copyright (c)  2024  Xiaomi Corporation (authors: Fangjun Kuang)
+
+using System.Linq;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using System.Text;
+using System;
+
+namespace SherpaOnnx
+{
+    public class CircularBuffer : IDisposable
+    {
+        public CircularBuffer(int capacity)
+        {
+            IntPtr h = SherpaOnnxCreateCircularBuffer(capacity);
+            _handle = new HandleRef(this, h);
+        }
+
+        public void Push(float[] data)
+        {
+            SherpaOnnxCircularBufferPush(_handle.Handle, data, data.Length);
+        }
+
+        public float[] Get(int startIndex, int n)
+        {
+            IntPtr p = SherpaOnnxCircularBufferGet(_handle.Handle, startIndex, n);
+
+            float[] ans = new float[n];
+            Marshal.Copy(p, ans, 0, n);
+
+            SherpaOnnxCircularBufferFree(p);
+
+            return ans;
+        }
+
+        public void Pop(int n)
+        {
+            SherpaOnnxCircularBufferPop(_handle.Handle, n);
+        }
+
+        public int Size
+        {
+          get
+          {
+              return SherpaOnnxCircularBufferSize(_handle.Handle);
+          }
+        }
+
+        public int Head
+        {
+          get
+          {
+              return SherpaOnnxCircularBufferHead(_handle.Handle);
+          }
+        }
+
+        public void Reset()
+        {
+            SherpaOnnxCircularBufferReset(_handle.Handle);
+        }
+
+        public void Dispose()
+        {
+            Cleanup();
+            // Prevent the object from being placed on the
+            // finalization queue
+            System.GC.SuppressFinalize(this);
+        }
+
+        ~CircularBuffer()
+        {
+            Cleanup();
+        }
+
+        private void Cleanup()
+        {
+            SherpaOnnxDestroyCircularBuffer(_handle.Handle);
+
+            // Don't permit the handle to be used again.
+            _handle = new HandleRef(this, IntPtr.Zero);
+        }
+
+        private HandleRef _handle;
+
+        [DllImport(Dll.Filename)]
+        private static extern IntPtr SherpaOnnxCreateCircularBuffer(int capacity);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxDestroyCircularBuffer(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxCircularBufferPush(IntPtr handle, float[] p, int n);
+
+        [DllImport(Dll.Filename)]
+        private static extern IntPtr SherpaOnnxCircularBufferGet(IntPtr handle, int startIndex, int n);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxCircularBufferFree(IntPtr p);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxCircularBufferPop(IntPtr handle, int n);
+
+        [DllImport(Dll.Filename)]
+        private static extern int SherpaOnnxCircularBufferSize(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern int SherpaOnnxCircularBufferHead(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxCircularBufferReset(IntPtr handle);
+    }
+}

+/// Copyright (c)  2024  Xiaomi Corporation (authors: Fangjun Kuang)
+
+using System.Linq;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using System.Text;
+using System;
+
+namespace SherpaOnnx
+{
+    [StructLayout(LayoutKind.Sequential)]
+    public struct SileroVadModelConfig
+    {
+        public SileroVadModelConfig()
+        {
+            Model = "";
+            Threshold = 0.5F;
+            MinSilenceDuration = 0.5F;
+            MinSpeechDuration = 0.25F;
+            WindowSize = 512;
+        }
+
+        [MarshalAs(UnmanagedType.LPStr)]
+        public string Model;
+
+        public float Threshold;
+
+        public float MinSilenceDuration;
+
+        public float MinSpeechDuration;
+
+        public int WindowSize;
+    }
+}

+/// Copyright (c)  2024  Xiaomi Corporation (authors: Fangjun Kuang)
+
+using System.Linq;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using System.Text;
+using System;
+
+namespace SherpaOnnx
+{
+    public class SpeechSegment
+    {
+      public SpeechSegment(IntPtr handle)
+      {
+            Impl impl = (Impl)Marshal.PtrToStructure(handle, typeof(Impl));
+
+            _start = impl.Start;
+
+            unsafe
+            {
+                float* t = (float*)impl.Samples;
+                _samples = new float[impl.Count];
+                fixed (float* pTarget = _samples)
+                {
+                    for (int i = 0; i < impl.Count; i++)
+                    {
+                        pTarget[i] = t[i];
+                    }
+                }
+            }
+      }
+
+      public int _start;
+      public int Start => _start;
+
+      private float[] _samples;
+      public float[] Samples => _samples;
+
+      [StructLayout(LayoutKind.Sequential)]
+      struct Impl
+      {
+          public int Start;
+          public IntPtr Samples;
+          public int Count;
+      }
+    }
+}

+/// Copyright (c)  2024  Xiaomi Corporation (authors: Fangjun Kuang)
+
+using System.Linq;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using System.Text;
+using System;
+
+namespace SherpaOnnx
+{
+    [StructLayout(LayoutKind.Sequential)]
+    public struct VadModelConfig
+    {
+        public VadModelConfig()
+        {
+            SileroVad = new SileroVadModelConfig();
+            SampleRate = 16000;
+            NumThreads = 1;
+            Provider = "cpu";
+            Debug = 0;
+        }
+
+        public SileroVadModelConfig SileroVad;
+
+        public int SampleRate;
+
+        public int NumThreads;
+
+        [MarshalAs(UnmanagedType.LPStr)]
+        public string Provider;
+
+        public int Debug;
+    }
+}
+

+/// Copyright (c)  2024  Xiaomi Corporation (authors: Fangjun Kuang)
+
+using System.Linq;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using System.Text;
+using System;
+
+namespace SherpaOnnx
+{
+    public class VoiceActivityDetector : IDisposable
+    {
+        public VoiceActivityDetector(VadModelConfig config, float bufferSizeInSeconds)
+        {
+            IntPtr h = SherpaOnnxCreateVoiceActivityDetector(ref config, bufferSizeInSeconds);
+            _handle = new HandleRef(this, h);
+        }
+
+        public void AcceptWaveform(float[] samples)
+        {
+            SherpaOnnxVoiceActivityDetectorAcceptWaveform(_handle.Handle, samples, samples.Length);
+        }
+
+        public bool IsEmpty()
+        {
+            return SherpaOnnxVoiceActivityDetectorEmpty(_handle.Handle) == 1;
+        }
+
+        public bool IsSpeechDetected()
+        {
+            return SherpaOnnxVoiceActivityDetectorDetected(_handle.Handle) == 1;
+        }
+
+        public void Pop()
+        {
+            SherpaOnnxVoiceActivityDetectorPop(_handle.Handle);
+        }
+
+        public SpeechSegment Front()
+        {
+            IntPtr p = SherpaOnnxVoiceActivityDetectorFront(_handle.Handle);
+
+            SpeechSegment segment = new SpeechSegment(p);
+
+            SherpaOnnxDestroySpeechSegment(p);
+
+            return segment;
+        }
+
+        public void Clear()
+        {
+            SherpaOnnxVoiceActivityDetectorClear(_handle.Handle);
+        }
+
+        public void Reset()
+        {
+            SherpaOnnxVoiceActivityDetectorReset(_handle.Handle);
+        }
+
+        public void Dispose()
+        {
+            Cleanup();
+            // Prevent the object from being placed on the
+            // finalization queue
+            System.GC.SuppressFinalize(this);
+        }
+
+        ~VoiceActivityDetector()
+        {
+            Cleanup();
+        }
+
+        private void Cleanup()
+        {
+            SherpaOnnxDestroyVoiceActivityDetector(_handle.Handle);
+
+            // Don't permit the handle to be used again.
+            _handle = new HandleRef(this, IntPtr.Zero);
+        }
+
+        private HandleRef _handle;
+
+        [DllImport(Dll.Filename)]
+        private static extern IntPtr SherpaOnnxCreateVoiceActivityDetector(ref VadModelConfig config, float bufferSizeInSeconds);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxDestroyVoiceActivityDetector(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxVoiceActivityDetectorAcceptWaveform(IntPtr handle, float[] samples, int n);
+
+        [DllImport(Dll.Filename)]
+        private static extern int SherpaOnnxVoiceActivityDetectorEmpty(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern int SherpaOnnxVoiceActivityDetectorDetected(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxVoiceActivityDetectorPop(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxVoiceActivityDetectorClear(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern IntPtr SherpaOnnxVoiceActivityDetectorFront(IntPtr handle);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxDestroySpeechSegment(IntPtr segment);
+
+        [DllImport(Dll.Filename)]
+        private static extern void SherpaOnnxVoiceActivityDetectorReset(IntPtr handle);
+
+    }
+}
+

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <RootNamespace>vad_non_streaming_asr_paraformer</RootNamespace>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <RestoreSources>/tmp/packages;$(RestoreSources);https://api.nuget.org/v3/index.json</RestoreSources>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="org.k2fsa.sherpa.onnx" Version="*" />
+  </ItemGroup>
+
+</Project>

@@ -4,7 +4,7 @@
     <PackageReadmeFile>README.md</PackageReadmeFile>
     <OutputType>Library</OutputType>
     <LangVersion>10.0</LangVersion>
-    <TargetFrameworks>netstandard2.0;netcoreapp3.1;net6.0;net7.0</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0</TargetFrameworks>
     <RuntimeIdentifiers>linux-x64;osx-x64;win-x64</RuntimeIdentifiers>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <AssemblyName>sherpa-onnx</AssemblyName>

@@ -3,7 +3,7 @@
     <PackageLicenseExpression>Apache-2.0</PackageLicenseExpression>
     <PackageReadmeFile>README.md</PackageReadmeFile>
     <OutputType>Library</OutputType>
-    <TargetFrameworks>netstandard2.0;netcoreapp3.1;net6.0;net7.0</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0</TargetFrameworks>
     <RuntimeIdentifier>{{ dotnet_rid }}</RuntimeIdentifier>
     <AssemblyName>sherpa-onnx</AssemblyName>
     <Version>{{ version }}</Version>