Add CXX API for speech enhancement GTCRN models (#1986)

.github/workflows/c-api.yaml

@@ -108,6 +108,8 @@ jobs:
           cp -v inp_16k.wav denoised-wavs
           cp -v enhanced_16k.wav denoised-wavs
 
+          rm $name
+
       - uses: actions/upload-artifact@v4
         with:
           name: denoised-wavs-${{ matrix.os }}

.github/workflows/cxx-api.yaml

@@ -81,6 +81,44 @@ jobs:
             otool -L ./install/lib/libsherpa-onnx-cxx-api.dylib
           fi
 
+      - name: Test Speech Enhancement (GTCRN)
+        shell: bash
+        run: |
+          name=speech-enhancement-gtcrn-cxx-api
+          g++ -std=c++17 -o $name ./cxx-api-examples/$name.cc \
+            -I ./build/install/include \
+            -L ./build/install/lib/ \
+            -l sherpa-onnx-cxx-api \
+            -l sherpa-onnx-c-api \
+            -l onnxruntime
+
+          ls -lh $name
+
+          export LD_LIBRARY_PATH=$PWD/build/install/lib:$LD_LIBRARY_PATH
+          export DYLD_LIBRARY_PATH=$PWD/build/install/lib:$DYLD_LIBRARY_PATH
+
+          if [[ ${{ matrix.os }} == ubuntu-latest || ${{ matrix.os }} == ubuntu-22.04-arm ]]; then
+            ldd ./$name
+            echo "----"
+            readelf -d ./$name
+          fi
+
+          curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/speech-enhancement-models/gtcrn_simple.onnx
+          curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/speech-enhancement-models/inp_16k.wav
+
+          ./$name
+
+          mkdir denoised-wavs
+          cp -v inp_16k.wav denoised-wavs
+          cp -v enhanced_16k.wav denoised-wavs
+
+          rm $name
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: denoised-wavs-cxx-${{ matrix.os }}
+          path: ./denoised-wavs/*.wav
+
       - name: Test FireRedAsr
         shell: bash
         run: |

cxx-api-examples/CMakeLists.txt

@@ -3,6 +3,9 @@ include_directories(${CMAKE_SOURCE_DIR})
 add_executable(streaming-zipformer-cxx-api ./streaming-zipformer-cxx-api.cc)
 target_link_libraries(streaming-zipformer-cxx-api sherpa-onnx-cxx-api)
 
+add_executable(speech-enhancement-gtcrn-cxx-api ./speech-enhancement-gtcrn-cxx-api.cc)
+target_link_libraries(speech-enhancement-gtcrn-cxx-api sherpa-onnx-cxx-api)
+
 add_executable(kws-cxx-api ./kws-cxx-api.cc)
 target_link_libraries(kws-cxx-api sherpa-onnx-cxx-api)
 

cxx-api-examples/kokoro-tts-zh-en-cxx-api.cc

@@ -1,4 +1,4 @@
-// cxx-api-examples/kokoro-tts-zh-en-cxx-api.c
+// cxx-api-examples/kokoro-tts-zh-en-cxx-api.cc
 //
 // Copyright (c)  2025  Xiaomi Corporation
 

cxx-api-examples/matcha-tts-en-cxx-api.cc

@@ -1,4 +1,4 @@
-// cxx-api-examples/matcha-tts-en-cxx-api.c
+// cxx-api-examples/matcha-tts-en-cxx-api.cc
 //
 // Copyright (c)  2025  Xiaomi Corporation
 

cxx-api-examples/matcha-tts-zh-cxx-api.cc

@@ -1,4 +1,4 @@
-// cxx-api-examples/matcha-tts-zh-cxx-api.c
+// cxx-api-examples/matcha-tts-zh-cxx-api.cc
 //
 // Copyright (c)  2025  Xiaomi Corporation
 

cxx-api-examples/speech-enhancement-gtcrn-cxx-api.cc

@@ -0,0 +1,65 @@
+// cxx-api-examples/speech-enhancement-gtcrn-cxx-api.cc
+//
+// Copyright (c)  2025  Xiaomi Corporation
+//
+// We assume you have pre-downloaded model
+// from
+// https://github.com/k2-fsa/sherpa-onnx/releases/tag/speech-enhancement-models
+//
+//
+// An example command to download
+// clang-format off
+/*
+wget https://github.com/k2-fsa/sherpa-onnx/releases/download/speech-enhancement-models/gtcrn_simple.onnx
+wget https://github.com/k2-fsa/sherpa-onnx/releases/download/speech-enhancement-models/inp_16k.wav
+*/
+// clang-format on
+#include <chrono>  // NOLINT
+#include <iostream>
+#include <string>
+
+#include "sherpa-onnx/c-api/cxx-api.h"
+
+int32_t main() {
+  using namespace sherpa_onnx::cxx;  // NOLINT
+
+  OfflineSpeechDenoiserConfig config;
+  std::string wav_filename = "./inp_16k.wav";
+  std::string out_wave_filename = "./enhanced_16k.wav";
+
+  config.model.gtcrn.model = "./gtcrn_simple.onnx";
+
+  auto sd = OfflineSpeechDenoiser::Create(config);
+  if (!sd.Get()) {
+    std::cerr << "Please check your config\n";
+    return -1;
+  }
+
+  Wave wave = ReadWave(wav_filename);
+  if (wave.samples.empty()) {
+    std::cerr << "Failed to read: '" << wav_filename << "'\n";
+    return -1;
+  }
+
+  std::cout << "Started\n";
+  const auto begin = std::chrono::steady_clock::now();
+  auto denoised =
+      sd.Run(wave.samples.data(), wave.samples.size(), wave.sample_rate);
+  const auto end = std::chrono::steady_clock::now();
+  std::cout << "Done\n";
+
+  WriteWave(out_wave_filename, {denoised.samples, denoised.sample_rate});
+
+  const float elapsed_seconds =
+      std::chrono::duration_cast<std::chrono::milliseconds>(end - begin)
+          .count() /
+      1000.;
+  float duration = wave.samples.size() / static_cast<float>(wave.sample_rate);
+  float rtf = elapsed_seconds / duration;
+
+  std::cout << "Saved to " << out_wave_filename << "\n";
+  printf("Duration: %.3fs\n", duration);
+  printf("Elapsed seconds: %.3fs\n", elapsed_seconds);
+  printf("(Real time factor) RTF = %.3f / %.3f = %.3f\n", elapsed_seconds,
+         duration, rtf);
+}

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

@@ -513,4 +513,49 @@ void KeywordSpotter::Reset(const OnlineStream *s) const {
   SherpaOnnxResetKeywordStream(p_, s->Get());
 }
 
+// ============================================================
+// For Offline Speech Enhancement
+// ============================================================
+
+OfflineSpeechDenoiser OfflineSpeechDenoiser::Create(
+    const OfflineSpeechDenoiserConfig &config) {
+  struct SherpaOnnxOfflineSpeechDenoiserConfig c;
+  memset(&c, 0, sizeof(c));
+
+  c.model.gtcrn.model = config.model.gtcrn.model.c_str();
+
+  c.model.num_threads = config.model.num_threads;
+  c.model.provider = config.model.provider.c_str();
+  c.model.debug = config.model.debug;
+
+  auto p = SherpaOnnxCreateOfflineSpeechDenoiser(&c);
+
+  return OfflineSpeechDenoiser(p);
+}
+
+void OfflineSpeechDenoiser::Destroy(
+    const SherpaOnnxOfflineSpeechDenoiser *p) const {
+  SherpaOnnxDestroyOfflineSpeechDenoiser(p);
+}
+
+OfflineSpeechDenoiser::OfflineSpeechDenoiser(
+    const SherpaOnnxOfflineSpeechDenoiser *p)
+    : MoveOnly<OfflineSpeechDenoiser, SherpaOnnxOfflineSpeechDenoiser>(p) {}
+
+DenoisedAudio OfflineSpeechDenoiser::Run(const float *samples, int32_t n,
+                                         int32_t sample_rate) const {
+  auto audio = SherpaOnnxOfflineSpeechDenoiserRun(p_, samples, n, sample_rate);
+
+  DenoisedAudio ans;
+  ans.samples = {audio->samples, audio->samples + audio->n};
+  ans.sample_rate = audio->sample_rate;
+  SherpaOnnxDestroyDenoisedAudio(audio);
+
+  return ans;
+}
+
+int32_t OfflineSpeechDenoiser::GetSampleRate() const {
+  return SherpaOnnxOfflineSpeechDenoiserGetSampleRate(p_);
+}
+
 }  // namespace sherpa_onnx::cxx

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

@@ -464,6 +464,42 @@ class SHERPA_ONNX_API KeywordSpotter
   explicit KeywordSpotter(const SherpaOnnxKeywordSpotter *p);
 };
 
+struct OfflineSpeechDenoiserGtcrnModelConfig {
+  std::string model;
+};
+
+struct OfflineSpeechDenoiserModelConfig {
+  OfflineSpeechDenoiserGtcrnModelConfig gtcrn;
+  int32_t num_threads = 1;
+  int32_t debug = false;
+  std::string provider = "cpu";
+};
+
+struct OfflineSpeechDenoiserConfig {
+  OfflineSpeechDenoiserModelConfig model;
+};
+
+struct DenoisedAudio {
+  std::vector<float> samples;  // in the range [-1, 1]
+  int32_t sample_rate;
+};
+
+class SHERPA_ONNX_API OfflineSpeechDenoiser
+    : public MoveOnly<OfflineSpeechDenoiser, SherpaOnnxOfflineSpeechDenoiser> {
+ public:
+  static OfflineSpeechDenoiser Create(
+      const OfflineSpeechDenoiserConfig &config);
+
+  void Destroy(const SherpaOnnxOfflineSpeechDenoiser *p) const;
+
+  DenoisedAudio Run(const float *samples, int32_t n, int32_t sample_rate) const;
+
+  int32_t GetSampleRate() const;
+
+ private:
+  explicit OfflineSpeechDenoiser(const SherpaOnnxOfflineSpeechDenoiser *p);
+};
+
 }  // namespace sherpa_onnx::cxx
 
 #endif  // SHERPA_ONNX_C_API_CXX_API_H_