Add timestamps and tokens for .Net's online models. (#690)

.github/workflows/aarch64-linux-gnu-shared.yaml

@@ -179,7 +179,7 @@ jobs:
 
       # https://huggingface.co/docs/hub/spaces-github-actions
       - name: Publish to huggingface
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa'
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && (github.event_name == 'push' && github.event_name == 'workflow_dispatch')
         env:
           HF_TOKEN: ${{ secrets.HF_TOKEN }}
         uses: nick-fields/retry@v3
@@ -210,7 +210,7 @@ jobs:
             git push https://csukuangfj:$HF_TOKEN@huggingface.co/csukuangfj/sherpa-onnx-libs main
 
       - name: Release pre-compiled binaries and libs for aarch64 linux
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/aarch64-linux-gnu-static.yaml

@@ -170,7 +170,7 @@ jobs:
 
       # https://huggingface.co/docs/hub/spaces-github-actions
       - name: Publish to huggingface
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa'
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && (github.event_name == 'push' && github.event_name == 'workflow_dispatch')
         env:
           HF_TOKEN: ${{ secrets.HF_TOKEN }}
         uses: nick-fields/retry@v3
@@ -201,7 +201,7 @@ jobs:
             git push https://csukuangfj:$HF_TOKEN@huggingface.co/csukuangfj/sherpa-onnx-libs main
 
       - name: Release pre-compiled binaries and libs for aarch64 linux
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/android.yaml

@@ -101,7 +101,7 @@ jobs:
 
       # https://huggingface.co/docs/hub/spaces-github-actions
       - name: Publish to huggingface
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && (github.event_name == 'push' && github.event_name == 'workflow_dispatch')
         env:
           HF_TOKEN: ${{ secrets.HF_TOKEN }}
         run: |

.github/workflows/arm-linux-gnueabihf.yaml

@@ -193,7 +193,7 @@ jobs:
 
       # https://huggingface.co/docs/hub/spaces-github-actions
       - name: Publish to huggingface
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa'
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && (github.event_name == 'push' && github.event_name == 'workflow_dispatch')
         env:
           HF_TOKEN: ${{ secrets.HF_TOKEN }}
         uses: nick-fields/retry@v3
@@ -224,7 +224,7 @@ jobs:
             git push https://csukuangfj:$HF_TOKEN@huggingface.co/csukuangfj/sherpa-onnx-libs main
 
       - name: Release pre-compiled binaries and libs for arm linux gnueabihf ${{ matrix.lib_type }}
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/dot-net.yaml

@@ -24,7 +24,7 @@ jobs:
           fetch-depth: 0
 
       - name: Setup .NET
-        uses: actions/setup-dotnet@v1
+        uses: actions/setup-dotnet@v4
         with:
           dotnet-version: |
             6.0.x

.github/workflows/linux-gpu.yaml

@@ -174,7 +174,7 @@ jobs:
           tar cjvf ${dst}.tar.bz2 $dst
 
       - name: Release pre-compiled binaries and libs for linux x64
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/linux.yaml

@@ -210,7 +210,6 @@ jobs:
           .github/scripts/test-online-transducer.sh
 
       - name: Copy files
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         shell: bash
         run: |
           SHERPA_ONNX_VERSION=v$(grep "SHERPA_ONNX_VERSION" ./CMakeLists.txt  | cut -d " " -f 2  | cut -d '"' -f 2)
@@ -227,7 +226,7 @@ jobs:
           tar cjvf ${dst}.tar.bz2 $dst
 
       - name: Release pre-compiled binaries and libs for linux x64
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/') && matrix.os == 'ubuntu-20.04' && matrix.gcc_version == '7'
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/') && matrix.os == 'ubuntu-20.04' && matrix.gcc_version == '7'
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/macos.yaml

@@ -175,7 +175,6 @@ jobs:
           .github/scripts/test-online-transducer.sh
 
       - name: Copy files
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         shell: bash
         run: |
           SHERPA_ONNX_VERSION=v$(grep "SHERPA_ONNX_VERSION" ./CMakeLists.txt  | cut -d " " -f 2  | cut -d '"' -f 2)
@@ -193,7 +192,7 @@ jobs:
           tar cjvf ${dst}.tar.bz2 $dst
 
       - name: Release pre-compiled binaries and libs for macOS
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/mfc.yaml

@@ -124,7 +124,7 @@ jobs:
           path: ./mfc-examples/${{ matrix.arch }}/Release/sherpa-onnx-non-streaming-asr-*.exe
 
       - name: Release pre-compiled binaries and libs for Windows ${{ matrix.arch }}
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true
@@ -132,7 +132,7 @@ jobs:
           file: ./mfc-examples/${{ matrix.arch }}/Release/sherpa-onnx-streaming-*.exe
 
       - name: Release pre-compiled binaries and libs for Windows ${{ matrix.arch }}
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/release-go.yaml

@@ -1,10 +1,6 @@
 name: release-go
 
 on:
-  push:
-    tags:
-      - '*'
-
   workflow_dispatch:
 
 concurrency:

.github/workflows/riscv64-linux.yaml

@@ -225,7 +225,7 @@ jobs:
 
       # https://huggingface.co/docs/hub/spaces-github-actions
       - name: Publish to huggingface
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa'
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && (github.event_name == 'push' && github.event_name == 'workflow_dispatch')
         env:
           HF_TOKEN: ${{ secrets.HF_TOKEN }}
         uses: nick-fields/retry@v3
@@ -269,7 +269,7 @@ jobs:
           path: sherpa-onnx-*linux-riscv64-static.tar.bz2
 
       - name: Release pre-compiled binaries and libs for riscv64 linux ${{ matrix.lib_type }}
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/run-python-test.yaml

@@ -63,7 +63,7 @@ jobs:
 
       - name: Run sccache-cache
         if: matrix.os == 'windows-latest'
-        uses: mozilla-actions/sccache-action@v0.0.3
+        uses: mozilla-actions/sccache-action@v0.0.4
         with:
           version: "v0.7.4"
 

.github/workflows/test-dot-net-nuget.yaml

@@ -33,7 +33,7 @@ jobs:
           fetch-depth: 0
 
       - name: Setup .NET 6.0
-        uses: actions/setup-dotnet@v1
+        uses: actions/setup-dotnet@v4
         with:
           dotnet-version: 6.0.x
 

.github/workflows/test-dot-net.yaml

@@ -137,7 +137,7 @@ jobs:
           path: /tmp/windows-x86
 
       - name: Setup .NET
-        uses: actions/setup-dotnet@v3
+        uses: actions/setup-dotnet@v4
         with:
           dotnet-version: |
             6.0.x

.github/workflows/windows-x64-cuda.yaml

@@ -133,7 +133,6 @@ jobs:
           .github/scripts/test-online-transducer.sh
 
       - name: Copy files
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         shell: bash
         run: |
           SHERPA_ONNX_VERSION=v$(grep "SHERPA_ONNX_VERSION" ./CMakeLists.txt  | cut -d " " -f 2  | cut -d '"' -f 2)
@@ -148,7 +147,7 @@ jobs:
           tar cjvf ${dst}.tar.bz2 $dst
 
       - name: Release pre-compiled binaries and libs for Windows x64 CUDA
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/windows-x64.yaml

@@ -154,7 +154,7 @@ jobs:
 
       # https://huggingface.co/docs/hub/spaces-github-actions
       - name: Publish to huggingface
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa'
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && (github.event_name == 'push' && github.event_name == 'workflow_dispatch')
         env:
           HF_TOKEN: ${{ secrets.HF_TOKEN }}
         uses: nick-fields/retry@v3
@@ -185,7 +185,7 @@ jobs:
             git push https://csukuangfj:$HF_TOKEN@huggingface.co/csukuangfj/sherpa-onnx-libs main
 
       - name: Release pre-compiled binaries and libs for Windows x64
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

.github/workflows/windows-x86.yaml

@@ -157,7 +157,7 @@ jobs:
 
       # https://huggingface.co/docs/hub/spaces-github-actions
       - name: Publish to huggingface
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa'
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && (github.event_name == 'push' && github.event_name == 'workflow_dispatch')
         env:
           HF_TOKEN: ${{ secrets.HF_TOKEN }}
         uses: nick-fields/retry@v3
@@ -188,7 +188,7 @@ jobs:
             git push https://csukuangfj:$HF_TOKEN@huggingface.co/csukuangfj/sherpa-onnx-libs main
 
       - name: Release pre-compiled binaries and libs for Windows x86
-        if: github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa' && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
+        if: (github.repository_owner == 'csukuangfj' || github.repository_owner == 'k2-fsa') && github.event_name == 'push' && contains(github.ref, 'refs/tags/')
         uses: svenstaro/upload-release-action@v2
         with:
           file_glob: true

cmake/kaldi-native-fbank.cmake

@@ -1,7 +1,8 @@
 function(download_kaldi_native_fbank)
   include(FetchContent)
 
-  set(kaldi_native_fbank_URL  "https://github.com/csukuangfj/kaldi-native-fbank/archive/refs/tags/v1.19.1.tar.gz")
+  set(kaldi_native_fbank_URL   "https://github.com/csukuangfj/kaldi-native-fbank/archive/refs/tags/v1.19.1.tar.gz")
+  set(kaldi_native_fbank_URL2  "https://hub.nuaa.cf/csukuangfj/kaldi-native-fbank/archive/refs/tags/v1.19.1.tar.gz")
   set(kaldi_native_fbank_URL2 "https://huggingface.co/csukuangfj/sherpa-onnx-cmake-deps/resolve/main/kaldi-native-fbank-1.19.1.tar.gz")
   set(kaldi_native_fbank_HASH "SHA256=0cae8cbb9ea42916b214e088912f9e8f2f648f54756b305f93f552382f31f904")
 
@@ -12,11 +13,11 @@ function(download_kaldi_native_fbank)
   # If you don't have access to the Internet,
   # please pre-download kaldi-native-fbank
   set(possible_file_locations
-    $ENV{HOME}/Downloads/kaldi-native-fbank-1.18.7.tar.gz
-    ${CMAKE_SOURCE_DIR}/kaldi-native-fbank-1.18.7.tar.gz
-    ${CMAKE_BINARY_DIR}/kaldi-native-fbank-1.18.7.tar.gz
-    /tmp/kaldi-native-fbank-1.18.7.tar.gz
-    /star-fj/fangjun/download/github/kaldi-native-fbank-1.18.7.tar.gz
+    $ENV{HOME}/Downloads/kaldi-native-fbank-1.19.1.tar.gz
+    ${CMAKE_SOURCE_DIR}/kaldi-native-fbank-1.19.1.tar.gz
+    ${CMAKE_BINARY_DIR}/kaldi-native-fbank-1.19.1.tar.gz
+    /tmp/kaldi-native-fbank-1.19.1.tar.gz
+    /star-fj/fangjun/download/github/kaldi-native-fbank-1.19.1.tar.gz
   )
 
   foreach(f IN LISTS possible_file_locations)

dotnet-examples/offline-decode-files/run-hotwords.sh

@@ -3,7 +3,7 @@
 set -ex
 
 if [ ! -d ./sherpa-onnx-zipformer-en-2023-04-01 ]; then
-  wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-zipformer-en-2023-04-01.tar.bz2
+  wget -q https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-zipformer-en-2023-04-01.tar.bz2
   tar xvf sherpa-onnx-zipformer-en-2023-04-01.tar.bz2
   rm sherpa-onnx-zipformer-en-2023-04-01.tar.bz2
 fi

dotnet-examples/offline-decode-files/run-zipformer.sh

@@ -3,7 +3,7 @@
 set -ex
 
 if [ ! -d ./sherpa-onnx-zipformer-en-2023-04-01 ]; then
-  wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-zipformer-en-2023-04-01.tar.bz2
+  wget -q https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-zipformer-en-2023-04-01.tar.bz2
   tar xvf sherpa-onnx-zipformer-en-2023-04-01.tar.bz2
   rm sherpa-onnx-zipformer-en-2023-04-01.tar.bz2
 fi

dotnet-examples/online-decode-files/Program.cs

@@ -226,10 +226,16 @@ to download pre-trained streaming models.
     // display results
     for (int i = 0; i != files.Length; ++i)
     {
-      var text = recognizer.GetResult(streams[i]).Text;
+      OnlineRecognizerResult r = recognizer.GetResult(streams[i]);
+      var text = r.Text;
+      var tokens = r.Tokens;
       Console.WriteLine("--------------------");
       Console.WriteLine(files[i]);
-      Console.WriteLine(text);
+      Console.WriteLine("text: {0}", text);
+      Console.WriteLine("tokens: [{0}]", string.Join(", ", tokens));
+      Console.Write("timestamps: [");
+      r.Timestamps.ToList().ForEach(i => Console.Write(String.Format("{0:0.00}", i) + ", "));
+      Console.WriteLine("]");
     }
     Console.WriteLine("--------------------");
   }

dotnet-examples/online-decode-files/run-transducer.sh

@@ -6,10 +6,8 @@
 
 set -ex
 if [ ! -d ./sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20 ]; then
-  GIT_LFS_SKIP_SMUDGE=1 git clone https://huggingface.co/csukuangfj/sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20
-  cd sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20
-  git lfs pull --include "*.onnx"
-  cd ..
+  wget -q https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20.tar.bz2
+  tar xvf sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20.tar.bz2
 fi
 
 dotnet run -c Release \

scripts/dotnet/online.cs

@@ -185,23 +185,82 @@ namespace SherpaOnnx
         while (*buffer != 0)
         {
           ++buffer;
+          length += 1;
         }
-        length = (int)(buffer - (byte*)impl.Text);
       }
 
       byte[] stringBuffer = new byte[length];
       Marshal.Copy(impl.Text, stringBuffer, 0, length);
       _text = Encoding.UTF8.GetString(stringBuffer);
+
+      _tokens = new String[impl.Count];
+
+      unsafe
+      {
+        byte* buf = (byte*)impl.Tokens;
+        for (int i = 0; i < impl.Count; i++)
+        {
+          length = 0;
+          byte* start = buf;
+          while (*buf != 0)
+          {
+            ++buf;
+            length += 1;
+          }
+          ++buf;
+
+          stringBuffer = new byte[length];
+          fixed (byte* pTarget = stringBuffer)
+          {
+            for (int k = 0; k < length; k++)
+            {
+              pTarget[k] = start[k];
+            }
+          }
+
+          _tokens[i] = Encoding.UTF8.GetString(stringBuffer);
+        }
+      }
+
+      unsafe
+      {
+        float* t = (float*)impl.Timestamps;
+        if (t != null)
+        {
+          _timestamps = new float[impl.Count];
+          fixed (float* pTarget = _timestamps)
+          {
+            for (int i = 0; i < impl.Count; i++)
+            {
+              pTarget[i] = t[i];
+            }
+          }
+        }
+        else
+        {
+          _timestamps = Array.Empty<float>();
+        }
+      }
     }
 
     [StructLayout(LayoutKind.Sequential)]
     struct Impl
     {
       public IntPtr Text;
+      public IntPtr Tokens;
+      public IntPtr TokensArr;
+      public IntPtr Timestamps;
+      public int Count;
     }
 
     private String _text;
     public String Text => _text;
+
+    private String[] _tokens;
+    public String[] Tokens => _tokens;
+
+    private float[] _timestamps;
+    public float[] Timestamps => _timestamps;
   }
 
   public class OnlineStream : IDisposable

sherpa-onnx/c-api/c-api.cc

@@ -162,15 +162,17 @@ const SherpaOnnxOnlineRecognizerResult *GetOnlineStreamResult(
   memset(r, 0, sizeof(SherpaOnnxOnlineRecognizerResult));
 
   // copy text
-  r->text = new char[text.size() + 1];
-  std::copy(text.begin(), text.end(), const_cast<char *>(r->text));
-  const_cast<char *>(r->text)[text.size()] = 0;
+  char *pText = new char[text.size() + 1];
+  std::copy(text.begin(), text.end(), pText);
+  pText[text.size()] = 0;
+  r->text = pText;
 
   // copy json
   const auto &json = result.AsJsonString();
-  r->json = new char[json.size() + 1];
-  std::copy(json.begin(), json.end(), const_cast<char *>(r->json));
-  const_cast<char *>(r->json)[json.size()] = 0;
+  char *pJson = new char[json.size() + 1];
+  std::copy(json.begin(), json.end(), pJson);
+  pJson[json.size()] = 0;
+  r->json = pJson;
 
   // copy tokens
   auto count = result.tokens.size();
@@ -183,15 +185,12 @@ const SherpaOnnxOnlineRecognizerResult *GetOnlineStreamResult(
 
     r->count = count;
     // Each word ends with nullptr
-    r->tokens = new char[total_length];
-    memset(reinterpret_cast<void *>(const_cast<char *>(r->tokens)), 0,
-           total_length);
+    char *tokens = new char[total_length]{};
     char **tokens_temp = new char *[r->count];
     int32_t pos = 0;
     for (int32_t i = 0; i < r->count; ++i) {
-      tokens_temp[i] = const_cast<char *>(r->tokens) + pos;
-      memcpy(reinterpret_cast<void *>(const_cast<char *>(r->tokens + pos)),
-             result.tokens[i].c_str(), result.tokens[i].size());
+      tokens_temp[i] = tokens + pos;
+      memcpy(tokens + pos, result.tokens[i].c_str(), result.tokens[i].size());
       // +1 to move past the null character
       pos += result.tokens[i].size() + 1;
     }
@@ -205,6 +204,7 @@ const SherpaOnnxOnlineRecognizerResult *GetOnlineStreamResult(
       r->timestamps = nullptr;
     }
 
+    r->tokens = tokens;
   } else {
     r->count = 0;
     r->timestamps = nullptr;
@@ -391,9 +391,10 @@ const SherpaOnnxOfflineRecognizerResult *GetOfflineStreamResult(
   auto r = new SherpaOnnxOfflineRecognizerResult;
   memset(r, 0, sizeof(SherpaOnnxOfflineRecognizerResult));
 
-  r->text = new char[text.size() + 1];
-  std::copy(text.begin(), text.end(), const_cast<char *>(r->text));
-  const_cast<char *>(r->text)[text.size()] = 0;
+  char *pText = new char[text.size() + 1];
+  std::copy(text.begin(), text.end(), pText);
+  pText[text.size()] = 0;
+  r->text = pText;
 
   if (!result.timestamps.empty()) {
     r->timestamps = new float[result.timestamps.size()];
@@ -530,15 +531,17 @@ const SherpaOnnxKeywordResult *GetKeywordResult(
   r->start_time = result.start_time;
 
   // copy keyword
-  r->keyword = new char[keyword.size() + 1];
-  std::copy(keyword.begin(), keyword.end(), const_cast<char *>(r->keyword));
-  const_cast<char *>(r->keyword)[keyword.size()] = 0;
+  char *pKeyword = new char[keyword.size() + 1];
+  std::copy(keyword.begin(), keyword.end(), pKeyword);
+  pKeyword[keyword.size()] = 0;
+  r->keyword = pKeyword;
 
   // copy json
   const auto &json = result.AsJsonString();
-  r->json = new char[json.size() + 1];
-  std::copy(json.begin(), json.end(), const_cast<char *>(r->json));
-  const_cast<char *>(r->json)[json.size()] = 0;
+  char *pJson = new char[json.size() + 1];
+  std::copy(json.begin(), json.end(), pJson);
+  pJson[json.size()] = 0;
+  r->json = pJson;
 
   // copy tokens
   auto count = result.tokens.size();
@@ -551,18 +554,16 @@ const SherpaOnnxKeywordResult *GetKeywordResult(
 
     r->count = count;
     // Each word ends with nullptr
-    r->tokens = new char[total_length];
-    memset(reinterpret_cast<void *>(const_cast<char *>(r->tokens)), 0,
-           total_length);
+    char *pTokens = new char[total_length]{};
     char **tokens_temp = new char *[r->count];
     int32_t pos = 0;
     for (int32_t i = 0; i < r->count; ++i) {
-      tokens_temp[i] = const_cast<char *>(r->tokens) + pos;
-      memcpy(reinterpret_cast<void *>(const_cast<char *>(r->tokens + pos)),
-             result.tokens[i].c_str(), result.tokens[i].size());
+      tokens_temp[i] = pTokens + pos;
+      memcpy(pTokens + pos, result.tokens[i].c_str(), result.tokens[i].size());
       // +1 to move past the null character
       pos += result.tokens[i].size() + 1;
     }
+    r->tokens = pTokens;
     r->tokens_arr = tokens_temp;
 
     if (!result.timestamps.empty()) {

sherpa-onnx/c-api/c-api.h

@@ -145,6 +145,10 @@ SHERPA_ONNX_API typedef struct SherpaOnnxOnlineRecognizerResult {
   const char *const *tokens_arr;
 
   // Pointer to continuous memory which holds timestamps
+  //
+  // Caution: If timestamp information is not available, this pointer is NULL.
+  // Please check whether it is NULL before you access it; otherwise, you would
+  // get segmentation fault.
   float *timestamps;
 
   // The number of tokens/timestamps in above pointer

sherpa-onnx/csrc/online-zipformer2-transducer-model.h

@@ -105,7 +105,7 @@ class OnlineZipformer2TransducerModel : public OnlineTransducerModel {
 
   int32_t context_size_ = 0;
   int32_t vocab_size_ = 0;
-  int32_t feature_dim_ = 0;
+  int32_t feature_dim_ = 80;
 };
 
 }  // namespace sherpa_onnx