Add VAD examples using ALSA for recording (#739)

sherpa-onnx/python/csrc/CMakeLists.txt

@@ -35,6 +35,7 @@ set(srcs
   vad-model-config.cc
   vad-model.cc
   voice-activity-detector.cc
+  wave-writer.cc
 )
 if(SHERPA_ONNX_HAS_ALSA)
   list(APPEND srcs ${CMAKE_SOURCE_DIR}/sherpa-onnx/csrc/alsa.cc alsa.cc)

sherpa-onnx/python/csrc/sherpa-onnx.cc

@@ -26,6 +26,7 @@
 #include "sherpa-onnx/python/csrc/vad-model-config.h"
 #include "sherpa-onnx/python/csrc/vad-model.h"
 #include "sherpa-onnx/python/csrc/voice-activity-detector.h"
+#include "sherpa-onnx/python/csrc/wave-writer.h"
 
 #if SHERPA_ONNX_ENABLE_TTS == 1
 #include "sherpa-onnx/python/csrc/offline-tts.h"
@@ -36,6 +37,8 @@ namespace sherpa_onnx {
 PYBIND11_MODULE(_sherpa_onnx, m) {
   m.doc() = "pybind11 binding of sherpa-onnx";
 
+  PybindWaveWriter(&m);
+
   PybindFeatures(&m);
   PybindOnlineCtcFstDecoderConfig(&m);
   PybindOnlineModelConfig(&m);

sherpa-onnx/python/csrc/wave-writer.cc

@@ -0,0 +1,27 @@
+// sherpa-onnx/python/csrc/wave-writer.cc
+//
+// Copyright (c)  2024  Xiaomi Corporation
+
+#include "sherpa-onnx/python/csrc/wave-writer.h"
+
+#include <string>
+#include <vector>
+
+#include "sherpa-onnx/csrc/wave-writer.h"
+
+namespace sherpa_onnx {
+
+void PybindWaveWriter(py::module *m) {
+  m->def(
+      "write_wave",
+      [](const std::string &filename, const std::vector<float> &samples,
+         int32_t sample_rate) -> bool {
+        bool ok =
+            WriteWave(filename, sample_rate, samples.data(), samples.size());
+
+        return ok;
+      },
+      py::arg("filename"), py::arg("samples"), py::arg("sample_rate"));
+}
+
+}  // namespace sherpa_onnx

sherpa-onnx/python/csrc/wave-writer.h

@@ -0,0 +1,16 @@
+// sherpa-onnx/python/csrc/wave-writer.h
+//
+// Copyright (c)  2024  Xiaomi Corporation
+
+#ifndef SHERPA_ONNX_PYTHON_CSRC_WAVE_WRITER_H_
+#define SHERPA_ONNX_PYTHON_CSRC_WAVE_WRITER_H_
+
+#include "sherpa-onnx/python/csrc/sherpa-onnx.h"
+
+namespace sherpa_onnx {
+
+void PybindWaveWriter(py::module *m);
+
+}
+
+#endif  // SHERPA_ONNX_PYTHON_CSRC_WAVE_WRITER_H_