Add C++ microphone examples for audio tagging (#749)

@@ -89,7 +89,7 @@ jobs:
           export PATH=/c/hostedtoolcache/windows/Python/3.8.10/x64/bin:$PATH
           export PATH=/c/hostedtoolcache/windows/Python/3.9.13/x64/bin:$PATH
           export PATH=/c/hostedtoolcache/windows/Python/3.10.11/x64/bin:$PATH
-          export PATH=/c/hostedtoolcache/windows/Python/3.11.8/x64/bin:$PATH
+          export PATH=/c/hostedtoolcache/windows/Python/3.11.9/x64/bin:$PATH
           export PATH=/c/hostedtoolcache/windows/Python/3.12.2/x64/bin:$PATH
 
           which sherpa-onnx

@@ -67,7 +67,7 @@ jobs:
           export PATH=/c/hostedtoolcache/windows/Python/3.8.10/x64/bin:$PATH
           export PATH=/c/hostedtoolcache/windows/Python/3.9.13/x64/bin:$PATH
           export PATH=/c/hostedtoolcache/windows/Python/3.10.11/x64/bin:$PATH
-          export PATH=/c/hostedtoolcache/windows/Python/3.11.8/x64/bin:$PATH
+          export PATH=/c/hostedtoolcache/windows/Python/3.11.9/x64/bin:$PATH
           export PATH=/c/hostedtoolcache/windows/Python/3.12.2/x64/bin:$PATH
 
           sherpa-onnx --help

@@ -2,23 +2,48 @@
 
 This repository supports running the following functions **locally**
 
-  - Speech-to-text (i.e., ASR)
+  - Speech-to-text (i.e., ASR); both streaming and non-streaming are supported
   - Text-to-speech (i.e., TTS)
   - Speaker identification
+  - Speaker verification
+  - Spoken language identification
+  - Audio tagging
+  - VAD (e.g., [silero-vad](https://github.com/snakers4/silero-vad))
 
 on the following platforms and operating systems:
 
-  - Linux, macOS, Windows
-  - Android
+  - x86, ``x86_64``, 32-bit ARM, 64-bit ARM (arm64, aarch64), RISC-V (riscv64)
+  - Linux, macOS, Windows, openKylin
+  - Android, WearOS
   - iOS
-  - Raspberry Pi
+  - NodeJS
+  - WebAssembly
+  - [Raspberry Pi](https://www.raspberrypi.com/)
+  - [RV1126](https://www.rock-chips.com/uploads/pdf/2022.8.26/191/RV1126%20Brief%20Datasheet.pdf)
+  - [LicheePi4A](https://sipeed.com/licheepi4a)
+  - [VisionFive 2](https://www.starfivetech.com/en/site/boards)
+  - [旭日X3派](https://developer.horizon.ai/api/v1/fileData/documents_pi/index.html)
   - etc
 
+with the following APIs
+
+  - C++
+  - C
+  - Python
+  - Go
+  - ``C#``
+  - Javascript
+  - Java
+  - Kotlin
+  - Swift
+
 # Useful links
 
 - Documentation: https://k2-fsa.github.io/sherpa/onnx/
 - APK for the text-to-speech engine: https://k2-fsa.github.io/sherpa/onnx/tts/apk-engine.html
 - APK for speaker identification: https://k2-fsa.github.io/sherpa/onnx/speaker-identification/apk.html
+- APK for speech recognition: https://github.com/k2-fsa/sherpa-onnx/releases/
+- Bilibili 演示视频: https://search.bilibili.com/all?keyword=%E6%96%B0%E4%B8%80%E4%BB%A3Kaldi
 
 # How to reach us
 

@@ -7,14 +7,22 @@ for usage.
 - [SherpaOnnx](./SherpaOnnx) It uses a streaming ASR model.
 
 - [SherpaOnnx2Pass](./SherpaOnnx2Pass) It uses a streaming ASR model
-  for the first pass and use a non-streaming ASR model for the second pass.
+  for the first pass and use a non-streaming ASR model for the second pass
 
-- [SherpaOnnxVad](./SherpaOnnxVad) It demonstrates how to use a VAD
+- [SherpaOnnxKws](./SherpaOnnxKws) It demonstrates how to use keyword spotting
 
-- [SherpaOnnxVadAsr](./SherpaOnnxVadAsr) It uses a VAD with a non-streaming
-  ASR model.
+- [SherpaOnnxSpeakerIdentification](./SherpaOnnxSpeakerIdentification) It demonstrates
+  how to use speaker identification
 
 - [SherpaOnnxTts](./SherpaOnnxTts) It is for standalone text-to-speech.
 
 - [SherpaOnnxTtsEngine](./SherpaOnnxTtsEngine) It is for text-to-speech engine;
    you can use it to replace the system TTS engine.
+
+- [SherpaOnnxVad](./SherpaOnnxVad) It demonstrates how to use a VAD
+
+- [SherpaOnnxVadAsr](./SherpaOnnxVadAsr) It uses a VAD with a non-streaming
+  ASR model.
+
+- [SherpaOnnxWebSocket](./SherpaOnnxWebSocket) It shows how to write a websocket
+  client for the Python streaming websocket server.

@@ -99,7 +99,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

@@ -50,6 +50,7 @@ def get_binaries():
         "sherpa-onnx-keyword-spotter",
         "sherpa-onnx-microphone",
         "sherpa-onnx-microphone-offline",
+        "sherpa-onnx-microphone-offline-audio-tagging",
         "sherpa-onnx-microphone-offline-speaker-identification",
         "sherpa-onnx-offline",
         "sherpa-onnx-offline-language-identification",
@@ -69,6 +70,7 @@ def get_binaries():
             "sherpa-onnx-alsa-offline-speaker-identification",
             "sherpa-onnx-offline-tts-play-alsa",
             "sherpa-onnx-vad-alsa",
+            "sherpa-onnx-alsa-offline-audio-tagging",
         ]
 
     if is_windows():

@@ -123,7 +123,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

@@ -39,7 +39,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

@@ -68,7 +68,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

@@ -264,6 +264,7 @@ if(SHERPA_ONNX_HAS_ALSA AND SHERPA_ONNX_ENABLE_BINARY)
   add_executable(sherpa-onnx-alsa-offline sherpa-onnx-alsa-offline.cc alsa.cc)
   add_executable(sherpa-onnx-alsa-offline-speaker-identification sherpa-onnx-alsa-offline-speaker-identification.cc alsa.cc)
   add_executable(sherpa-onnx-vad-alsa sherpa-onnx-vad-alsa.cc alsa.cc)
+  add_executable(sherpa-onnx-alsa-offline-audio-tagging sherpa-onnx-alsa-offline-audio-tagging.cc alsa.cc)
 
 
   if(SHERPA_ONNX_ENABLE_TTS)
@@ -276,6 +277,7 @@ if(SHERPA_ONNX_HAS_ALSA AND SHERPA_ONNX_ENABLE_BINARY)
     sherpa-onnx-alsa-offline-speaker-identification
     sherpa-onnx-keyword-spotter-alsa
     sherpa-onnx-vad-alsa
+    sherpa-onnx-alsa-offline-audio-tagging
   )
 
   if(SHERPA_ONNX_ENABLE_TTS)
@@ -354,6 +356,11 @@ if(SHERPA_ONNX_ENABLE_PORTAUDIO AND SHERPA_ONNX_ENABLE_BINARY)
     microphone.cc
   )
 
+  add_executable(sherpa-onnx-microphone-offline-audio-tagging
+    sherpa-onnx-microphone-offline-audio-tagging.cc
+    microphone.cc
+  )
+
   if(BUILD_SHARED_LIBS)
     set(PA_LIB portaudio)
   else()
@@ -365,6 +372,7 @@ if(SHERPA_ONNX_ENABLE_PORTAUDIO AND SHERPA_ONNX_ENABLE_BINARY)
     sherpa-onnx-keyword-spotter-microphone
     sherpa-onnx-microphone-offline
     sherpa-onnx-microphone-offline-speaker-identification
+    sherpa-onnx-microphone-offline-audio-tagging
     sherpa-onnx-vad-microphone
     sherpa-onnx-vad-microphone-offline-asr
   )

@@ -35,7 +35,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

+// sherpa-onnx/csrc/sherpa-onnx-alsa-offline-audio-tagging.cc
+//
+// Copyright (c)  2022-2024  Xiaomi Corporation
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <algorithm>
+#include <mutex>   // NOLINT
+#include <thread>  // NOLINT
+
+#include "sherpa-onnx/csrc/alsa.h"
+#include "sherpa-onnx/csrc/audio-tagging.h"
+#include "sherpa-onnx/csrc/macros.h"
+
+enum class State {
+  kIdle,
+  kRecording,
+  kDecoding,
+};
+
+State state = State::kIdle;
+
+// true to stop the program and exit
+bool stop = false;
+
+std::vector<float> samples;
+std::mutex samples_mutex;
+
+static void DetectKeyPress() {
+  SHERPA_ONNX_LOGE("Press Enter to start");
+  int32_t key;
+  while (!stop && (key = getchar())) {
+    if (key != 0x0a) {
+      continue;
+    }
+
+    switch (state) {
+      case State::kIdle:
+        SHERPA_ONNX_LOGE("Start recording. Press Enter to stop recording");
+        state = State::kRecording;
+        {
+          std::lock_guard<std::mutex> lock(samples_mutex);
+          samples.clear();
+        }
+        break;
+      case State::kRecording:
+        SHERPA_ONNX_LOGE("Stop recording. Decoding ...");
+        state = State::kDecoding;
+        break;
+      case State::kDecoding:
+        break;
+    }
+  }
+}
+
+static void Record(const char *device_name, int32_t expected_sample_rate) {
+  sherpa_onnx::Alsa alsa(device_name);
+
+  if (alsa.GetExpectedSampleRate() != expected_sample_rate) {
+    fprintf(stderr, "sample rate: %d != %d\n", alsa.GetExpectedSampleRate(),
+            expected_sample_rate);
+    exit(-1);
+  }
+
+  int32_t chunk = 0.1 * alsa.GetActualSampleRate();
+  while (!stop) {
+    const std::vector<float> &s = alsa.Read(chunk);
+    std::lock_guard<std::mutex> lock(samples_mutex);
+    samples.insert(samples.end(), s.begin(), s.end());
+  }
+}
+
+static void Handler(int32_t sig) {
+  stop = true;
+  fprintf(stderr, "\nCaught Ctrl + C. Press Enter to exit\n");
+}
+
+int32_t main(int32_t argc, char *argv[]) {
+  signal(SIGINT, Handler);
+
+  const char *kUsageMessage = R"usage(
+Audio tagging from microphone (Linux only).
+Usage:
+
+wget https://github.com/k2-fsa/sherpa-onnx/releases/download/audio-tagging-models/sherpa-onnx-zipformer-audio-tagging-2024-04-09.tar.bz2
+tar xvf sherpa-onnx-zipformer-audio-tagging-2024-04-09.tar.bz2
+rm sherpa-onnx-zipformer-audio-tagging-2024-04-09.tar.bz2
+
+./bin/sherpa-onnx-alsa-offline-audio-tagging \
+  --zipformer-model=./sherpa-onnx-zipformer-audio-tagging-2024-04-09/model.onnx \
+  --labels=./sherpa-onnx-zipformer-audio-tagging-2024-04-09/class_labels_indices.csv \
+    device_name
+
+Please refer to
+https://github.com/k2-fsa/sherpa-onnx/releases/tag/audio-tagging-models
+for a list of pre-trained models to download.
+
+The device name specifies which microphone to use in case there are several
+on your system. You can use
+
+  arecord -l
+
+to find all available microphones on your computer. For instance, if it outputs
+
+**** List of CAPTURE Hardware Devices ****
+card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
+  Subdevices: 1/1
+  Subdevice #0: subdevice #0
+
+and if you want to select card 3 and device 0 on that card, please use:
+
+  plughw:3,0
+
+as the device_name.
+)usage";
+
+  sherpa_onnx::ParseOptions po(kUsageMessage);
+  sherpa_onnx::AudioTaggingConfig config;
+  config.Register(&po);
+
+  po.Read(argc, argv);
+  if (po.NumArgs() != 1) {
+    fprintf(stderr, "Please provide only 1 argument: the device name\n");
+    po.PrintUsage();
+    exit(EXIT_FAILURE);
+  }
+
+  fprintf(stderr, "%s\n", config.ToString().c_str());
+
+  if (!config.Validate()) {
+    fprintf(stderr, "Errors in config!\n");
+    return -1;
+  }
+
+  SHERPA_ONNX_LOGE("Creating audio tagger ...");
+  sherpa_onnx::AudioTagging tagger(config);
+  SHERPA_ONNX_LOGE("Audio tagger created created!");
+
+  std::string device_name = po.GetArg(1);
+  fprintf(stderr, "Use recording device: %s\n", device_name.c_str());
+
+  int32_t sample_rate = 16000;  // fixed to 16000Hz for all models from icefall
+
+  std::thread t2(Record, device_name.c_str(), sample_rate);
+  using namespace std::chrono_literals;  // NOLINT
+  std::this_thread::sleep_for(100ms);    // sleep for 100ms
+  std::thread t(DetectKeyPress);
+
+  while (!stop) {
+    switch (state) {
+      case State::kIdle:
+        break;
+      case State::kRecording:
+        break;
+      case State::kDecoding: {
+        std::vector<float> buf;
+        {
+          std::lock_guard<std::mutex> lock(samples_mutex);
+          buf = std::move(samples);
+        }
+        SHERPA_ONNX_LOGE("Computing...");
+        auto s = tagger.CreateStream();
+        s->AcceptWaveform(sample_rate, buf.data(), buf.size());
+        auto results = tagger.Compute(s.get());
+        SHERPA_ONNX_LOGE("Result is:");
+
+        int32_t i = 0;
+        std::ostringstream os;
+        for (const auto &event : results) {
+          os << i << ": " << event.ToString() << "\n";
+          i += 1;
+        }
+
+        SHERPA_ONNX_LOGE("\n%s\n", os.str().c_str());
+
+        state = State::kIdle;
+        SHERPA_ONNX_LOGE("Press Enter to start");
+        break;
+      }
+    }
+
+    std::this_thread::sleep_for(20ms);  // sleep for 20ms
+  }
+  t.join();
+  t2.join();
+
+  return 0;
+}

@@ -71,8 +71,8 @@ static void Record(const char *device_name, int32_t expected_sample_rate) {
 
   int32_t chunk = 0.1 * alsa.GetActualSampleRate();
   while (!stop) {
-    std::lock_guard<std::mutex> lock(samples_mutex);
     const std::vector<float> &s = alsa.Read(chunk);
+    std::lock_guard<std::mutex> lock(samples_mutex);
     samples.insert(samples.end(), s.begin(), s.end());
   }
 }
@@ -193,7 +193,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
   plughw:3,0
 as the device_name.
 

@@ -68,8 +68,8 @@ static void Record(const char *device_name, int32_t expected_sample_rate) {
 
   int32_t chunk = 0.1 * alsa.GetActualSampleRate();
   while (!stop) {
-    std::lock_guard<std::mutex> lock(samples_mutex);
     const std::vector<float> &s = alsa.Read(chunk);
+    std::lock_guard<std::mutex> lock(samples_mutex);
     samples.insert(samples.end(), s.begin(), s.end());
   }
 }
@@ -119,7 +119,7 @@ https://k2-fsa.github.io/sherpa/onnx/pretrained_models/index.html
 for a list of pre-trained models to download.
 
 The device name specifies which microphone to use in case there are several
-on you system. You can use
+on your system. You can use
 
   arecord -l
 
@@ -130,7 +130,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

@@ -52,7 +52,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

@@ -40,7 +40,7 @@ https://k2-fsa.github.io/sherpa/onnx/kws/pretrained_models/index.html
 for a list of pre-trained models to download.
 
 The device name specifies which microphone to use in case there are several
-on you system. You can use
+on your system. You can use
 
   arecord -l
 
@@ -51,7 +51,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

@@ -10,10 +10,11 @@
 
 #include "portaudio.h"  // NOLINT
 #include "sherpa-onnx/csrc/display.h"
-#include "sherpa-onnx/csrc/microphone.h"
 #include "sherpa-onnx/csrc/keyword-spotter.h"
+#include "sherpa-onnx/csrc/microphone.h"
 
 bool stop = false;
+float mic_sample_rate = 16000;
 
 static int32_t RecordCallback(const void *input_buffer,
                               void * /*output_buffer*/,
@@ -23,7 +24,8 @@ static int32_t RecordCallback(const void *input_buffer,
                               void *user_data) {
   auto stream = reinterpret_cast<sherpa_onnx::OnlineStream *>(user_data);
 
-  stream->AcceptWaveform(16000, reinterpret_cast<const float *>(input_buffer),
+  stream->AcceptWaveform(mic_sample_rate,
+                         reinterpret_cast<const float *>(input_buffer),
                          frames_per_buffer);
 
   return stop ? paComplete : paContinue;
@@ -80,14 +82,31 @@ for a list of pre-trained models to download.
   PaDeviceIndex num_devices = Pa_GetDeviceCount();
   fprintf(stderr, "Num devices: %d\n", num_devices);
 
-  PaStreamParameters param;
+  int32_t device_index = Pa_GetDefaultInputDevice();
 
-  param.device = Pa_GetDefaultInputDevice();
-  if (param.device == paNoDevice) {
+  if (device_index == paNoDevice) {
     fprintf(stderr, "No default input device found\n");
+    fprintf(stderr, "If you are using Linux, please switch to \n");
+    fprintf(stderr, " ./bin/sherpa-onnx-keyword-spotter-alsa \n");
     exit(EXIT_FAILURE);
   }
-  fprintf(stderr, "Use default device: %d\n", param.device);
+
+  const char *pDeviceIndex = std::getenv("SHERPA_ONNX_MIC_DEVICE");
+  if (pDeviceIndex) {
+    fprintf(stderr, "Use specified device: %s\n", pDeviceIndex);
+    device_index = atoi(pDeviceIndex);
+  }
+
+  for (int32_t i = 0; i != num_devices; ++i) {
+    const PaDeviceInfo *info = Pa_GetDeviceInfo(i);
+    fprintf(stderr, " %s %d %s\n", (i == device_index) ? "*" : " ", i,
+            info->name);
+  }
+
+  PaStreamParameters param;
+  param.device = device_index;
+
+  fprintf(stderr, "Use device: %d\n", param.device);
 
   const PaDeviceInfo *info = Pa_GetDeviceInfo(param.device);
   fprintf(stderr, "  Name: %s\n", info->name);
@@ -98,12 +117,19 @@ for a list of pre-trained models to download.
 
   param.suggestedLatency = info->defaultLowInputLatency;
   param.hostApiSpecificStreamInfo = nullptr;
+
+  const char *pSampleRateStr = std::getenv("SHERPA_ONNX_MIC_SAMPLE_RATE");
+  if (pSampleRateStr) {
+    fprintf(stderr, "Use sample rate %f for mic\n", mic_sample_rate);
+    mic_sample_rate = atof(pSampleRateStr);
+  }
+
   float sample_rate = 16000;
 
   PaStream *stream;
   PaError err =
       Pa_OpenStream(&stream, &param, nullptr, /* &outputParameters, */
-                    sample_rate,
+                    mic_sample_rate,
                     0,          // frames per buffer
                     paClipOff,  // we won't output out of range samples
                                 // so don't bother clipping them

+// sherpa-onnx/csrc/sherpa-onnx-microphone-offline-audio-tagging.cc
+//
+// Copyright (c)  2024  Xiaomi Corporation
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <algorithm>
+#include <cctype>  // std::tolower
+#include <mutex>   // NOLINT
+#include <thread>  // NOLINT
+
+#include "portaudio.h"  // NOLINT
+#include "sherpa-onnx/csrc/audio-tagging.h"
+#include "sherpa-onnx/csrc/macros.h"
+#include "sherpa-onnx/csrc/microphone.h"
+
+enum class State {
+  kIdle,
+  kRecording,
+  kDecoding,
+};
+
+State state = State::kIdle;
+
+// true to stop the program and exit
+bool stop = false;
+
+std::vector<float> samples;
+std::mutex samples_mutex;
+
+static void DetectKeyPress() {
+  SHERPA_ONNX_LOGE("Press Enter to start");
+  int32_t key;
+  while (!stop && (key = getchar())) {
+    if (key != 0x0a) {
+      continue;
+    }
+
+    switch (state) {
+      case State::kIdle:
+        SHERPA_ONNX_LOGE("Start recording. Press Enter to stop recording");
+        state = State::kRecording;
+        {
+          std::lock_guard<std::mutex> lock(samples_mutex);
+          samples.clear();
+        }
+        break;
+      case State::kRecording:
+        SHERPA_ONNX_LOGE("Stop recording. Decoding ...");
+        state = State::kDecoding;
+        break;
+      case State::kDecoding:
+        break;
+    }
+  }
+}
+
+static int32_t RecordCallback(const void *input_buffer,
+                              void * /*output_buffer*/,
+                              unsigned long frames_per_buffer,  // NOLINT
+                              const PaStreamCallbackTimeInfo * /*time_info*/,
+                              PaStreamCallbackFlags /*status_flags*/,
+                              void *user_data) {
+  std::lock_guard<std::mutex> lock(samples_mutex);
+
+  auto p = reinterpret_cast<const float *>(input_buffer);
+  samples.insert(samples.end(), p, p + frames_per_buffer);
+
+  return stop ? paComplete : paContinue;
+}
+
+static void Handler(int32_t sig) {
+  stop = true;
+  fprintf(stderr, "\nCaught Ctrl + C. Press Enter to exit\n");
+}
+
+int32_t main(int32_t argc, char *argv[]) {
+  signal(SIGINT, Handler);
+
+  const char *kUsageMessage = R"usage(
+Audio tagging from microphone.
+Usage:
+
+wget https://github.com/k2-fsa/sherpa-onnx/releases/download/audio-tagging-models/sherpa-onnx-zipformer-audio-tagging-2024-04-09.tar.bz2
+tar xvf sherpa-onnx-zipformer-audio-tagging-2024-04-09.tar.bz2
+rm sherpa-onnx-zipformer-audio-tagging-2024-04-09.tar.bz2
+
+./bin/sherpa-onnx-microphone-offline-audio-tagging \
+  --zipformer-model=./sherpa-onnx-zipformer-audio-tagging-2024-04-09/model.onnx \
+  --labels=./sherpa-onnx-zipformer-audio-tagging-2024-04-09/class_labels_indices.csv
+
+Please see
+https://github.com/k2-fsa/sherpa-onnx/releases/tag/audio-tagging-models
+for more models.
+)usage";
+
+  sherpa_onnx::ParseOptions po(kUsageMessage);
+  sherpa_onnx::AudioTaggingConfig config;
+  config.Register(&po);
+
+  po.Read(argc, argv);
+  if (po.NumArgs() != 0) {
+    fprintf(stderr, "\nThis program does not support positional arguments\n\n");
+    po.PrintUsage();
+    exit(EXIT_FAILURE);
+  }
+
+  fprintf(stderr, "%s\n", config.ToString().c_str());
+
+  if (!config.Validate()) {
+    fprintf(stderr, "Errors in config!\n");
+    return -1;
+  }
+
+  SHERPA_ONNX_LOGE("Creating audio tagger ...");
+  sherpa_onnx::AudioTagging tagger(config);
+  SHERPA_ONNX_LOGE("Audio tagger created created!");
+
+  sherpa_onnx::Microphone mic;
+
+  PaDeviceIndex num_devices = Pa_GetDeviceCount();
+  fprintf(stderr, "Num devices: %d\n", num_devices);
+
+  int32_t device_index = Pa_GetDefaultInputDevice();
+
+  if (device_index == paNoDevice) {
+    fprintf(stderr, "No default input device found\n");
+    fprintf(stderr, "If you are using Linux, please switch to \n");
+    fprintf(stderr, " ./bin/sherpa-onnx-alsa-offline-audio-tagging \n");
+    exit(EXIT_FAILURE);
+  }
+
+  const char *pDeviceIndex = std::getenv("SHERPA_ONNX_MIC_DEVICE");
+  if (pDeviceIndex) {
+    fprintf(stderr, "Use specified device: %s\n", pDeviceIndex);
+    device_index = atoi(pDeviceIndex);
+  }
+
+  for (int32_t i = 0; i != num_devices; ++i) {
+    const PaDeviceInfo *info = Pa_GetDeviceInfo(i);
+    fprintf(stderr, " %s %d %s\n", (i == device_index) ? "*" : " ", i,
+            info->name);
+  }
+
+  PaStreamParameters param;
+  param.device = device_index;
+
+  fprintf(stderr, "Use device: %d\n", param.device);
+
+  const PaDeviceInfo *info = Pa_GetDeviceInfo(param.device);
+  fprintf(stderr, "  Name: %s\n", info->name);
+  fprintf(stderr, "  Max input channels: %d\n", info->maxInputChannels);
+
+  param.channelCount = 1;
+  param.sampleFormat = paFloat32;
+
+  param.suggestedLatency = info->defaultLowInputLatency;
+  param.hostApiSpecificStreamInfo = nullptr;
+  float mic_sample_rate = 16000;
+  const char *pSampleRateStr = std::getenv("SHERPA_ONNX_MIC_SAMPLE_RATE");
+  if (pSampleRateStr) {
+    fprintf(stderr, "Use sample rate %f for mic\n", mic_sample_rate);
+    mic_sample_rate = atof(pSampleRateStr);
+  }
+
+  float sample_rate = 16000;
+
+  PaStream *stream;
+  PaError err =
+      Pa_OpenStream(&stream, &param, nullptr, /* &outputParameters, */
+                    mic_sample_rate,
+                    0,          // frames per buffer
+                    paClipOff,  // we won't output out of range samples
+                                // so don't bother clipping them
+                    RecordCallback, nullptr);
+  if (err != paNoError) {
+    fprintf(stderr, "portaudio error: %s\n", Pa_GetErrorText(err));
+    exit(EXIT_FAILURE);
+  }
+
+  err = Pa_StartStream(stream);
+  fprintf(stderr, "Started\n");
+
+  if (err != paNoError) {
+    fprintf(stderr, "portaudio error: %s\n", Pa_GetErrorText(err));
+    exit(EXIT_FAILURE);
+  }
+
+  std::thread t(DetectKeyPress);
+  while (!stop) {
+    switch (state) {
+      case State::kIdle:
+        break;
+      case State::kRecording:
+        break;
+      case State::kDecoding: {
+        std::vector<float> buf;
+        {
+          std::lock_guard<std::mutex> lock(samples_mutex);
+          buf = std::move(samples);
+        }
+
+        SHERPA_ONNX_LOGE("Computing...");
+        auto s = tagger.CreateStream();
+        s->AcceptWaveform(mic_sample_rate, buf.data(), buf.size());
+        auto results = tagger.Compute(s.get());
+
+        SHERPA_ONNX_LOGE("Result is:");
+
+        int32_t i = 0;
+        std::ostringstream os;
+        for (const auto &event : results) {
+          os << i << ": " << event.ToString() << "\n";
+          i += 1;
+        }
+
+        SHERPA_ONNX_LOGE("\n%s\n", os.str().c_str());
+
+        state = State::kIdle;
+        SHERPA_ONNX_LOGE("Press Enter to start");
+        break;
+      }
+    }
+
+    Pa_Sleep(20);  // sleep for 20ms
+  }
+  t.join();
+
+  err = Pa_CloseStream(stream);
+  if (err != paNoError) {
+    fprintf(stderr, "portaudio error: %s\n", Pa_GetErrorText(err));
+    exit(EXIT_FAILURE);
+  }
+
+  return 0;
+}

@@ -223,14 +223,31 @@ Note that `zh` means Chinese, while `en` means English.
   PaDeviceIndex num_devices = Pa_GetDeviceCount();
   fprintf(stderr, "Num devices: %d\n", num_devices);
 
-  PaStreamParameters param;
-
-  param.device = Pa_GetDefaultInputDevice();
-  if (param.device == paNoDevice) {
+  int32_t device_index = Pa_GetDefaultInputDevice();
+  if (device_index == paNoDevice) {
     fprintf(stderr, "No default input device found\n");
+    fprintf(stderr, "If you are using Linux, please switch to \n");
+    fprintf(stderr,
+            " ./bin/sherpa-onnx-alsa-offline-speaker-identification \n");
     exit(EXIT_FAILURE);
   }
-  fprintf(stderr, "Use default device: %d\n", param.device);
+
+  const char *pDeviceIndex = std::getenv("SHERPA_ONNX_MIC_DEVICE");
+  if (pDeviceIndex) {
+    fprintf(stderr, "Use specified device: %s\n", pDeviceIndex);
+    device_index = atoi(pDeviceIndex);
+  }
+
+  for (int32_t i = 0; i != num_devices; ++i) {
+    const PaDeviceInfo *info = Pa_GetDeviceInfo(i);
+    fprintf(stderr, " %s %d %s\n", (i == device_index) ? "*" : " ", i,
+            info->name);
+  }
+
+  PaStreamParameters param;
+  param.device = device_index;
+
+  fprintf(stderr, "Use device: %d\n", param.device);
 
   const PaDeviceInfo *info = Pa_GetDeviceInfo(param.device);
   fprintf(stderr, "  Name: %s\n", info->name);
@@ -241,12 +258,18 @@ Note that `zh` means Chinese, while `en` means English.
 
   param.suggestedLatency = info->defaultLowInputLatency;
   param.hostApiSpecificStreamInfo = nullptr;
+  float mic_sample_rate = 16000;
+  const char *pSampleRateStr = std::getenv("SHERPA_ONNX_MIC_SAMPLE_RATE");
+  if (pSampleRateStr) {
+    fprintf(stderr, "Use sample rate %f for mic\n", mic_sample_rate);
+    mic_sample_rate = atof(pSampleRateStr);
+  }
   float sample_rate = 16000;
 
   PaStream *stream;
   PaError err =
       Pa_OpenStream(&stream, &param, nullptr, /* &outputParameters, */
-                    sample_rate,
+                    mic_sample_rate,
                     0,          // frames per buffer
                     paClipOff,  // we won't output out of range samples
                                 // so don't bother clipping them
@@ -279,7 +302,7 @@ Note that `zh` means Chinese, while `en` means English.
         }
 
         auto s = extractor.CreateStream();
-        s->AcceptWaveform(sample_rate, buf.data(), buf.size());
+        s->AcceptWaveform(mic_sample_rate, buf.data(), buf.size());
         s->InputFinished();
         auto embedding = extractor.Compute(s.get());
         auto name = manager.Search(embedding.data(), threshold);

@@ -139,14 +139,31 @@ for a list of pre-trained models to download.
   PaDeviceIndex num_devices = Pa_GetDeviceCount();
   fprintf(stderr, "Num devices: %d\n", num_devices);
 
-  PaStreamParameters param;
+  int32_t device_index = Pa_GetDefaultInputDevice();
 
-  param.device = Pa_GetDefaultInputDevice();
-  if (param.device == paNoDevice) {
+  if (device_index == paNoDevice) {
     fprintf(stderr, "No default input device found\n");
+    fprintf(stderr, "If you are using Linux, please switch to \n");
+    fprintf(stderr, " ./bin/sherpa-onnx-alsa-offline \n");
     exit(EXIT_FAILURE);
   }
-  fprintf(stderr, "Use default device: %d\n", param.device);
+
+  const char *pDeviceIndex = std::getenv("SHERPA_ONNX_MIC_DEVICE");
+  if (pDeviceIndex) {
+    fprintf(stderr, "Use specified device: %s\n", pDeviceIndex);
+    device_index = atoi(pDeviceIndex);
+  }
+
+  for (int32_t i = 0; i != num_devices; ++i) {
+    const PaDeviceInfo *info = Pa_GetDeviceInfo(i);
+    fprintf(stderr, " %s %d %s\n", (i == device_index) ? "*" : " ", i,
+            info->name);
+  }
+
+  PaStreamParameters param;
+  param.device = device_index;
+
+  fprintf(stderr, "Use device: %d\n", param.device);
 
   const PaDeviceInfo *info = Pa_GetDeviceInfo(param.device);
   fprintf(stderr, "  Name: %s\n", info->name);
@@ -157,12 +174,18 @@ for a list of pre-trained models to download.
 
   param.suggestedLatency = info->defaultLowInputLatency;
   param.hostApiSpecificStreamInfo = nullptr;
+  float mic_sample_rate = 16000;
+  const char *pSampleRateStr = std::getenv("SHERPA_ONNX_MIC_SAMPLE_RATE");
+  if (pSampleRateStr) {
+    fprintf(stderr, "Use sample rate %f for mic\n", mic_sample_rate);
+    mic_sample_rate = atof(pSampleRateStr);
+  }
   float sample_rate = 16000;
 
   PaStream *stream;
   PaError err =
       Pa_OpenStream(&stream, &param, nullptr, /* &outputParameters, */
-                    sample_rate,
+                    mic_sample_rate,
                     0,          // frames per buffer
                     paClipOff,  // we won't output out of range samples
                                 // so don't bother clipping them
@@ -195,7 +218,7 @@ for a list of pre-trained models to download.
         }
 
         auto s = recognizer.CreateStream();
-        s->AcceptWaveform(sample_rate, buf.data(), buf.size());
+        s->AcceptWaveform(mic_sample_rate, buf.data(), buf.size());
         recognizer.DecodeStream(s.get());
         SHERPA_ONNX_LOGE("Decoding Done! Result is:");
         SHERPA_ONNX_LOGE("%s", s->GetResult().text.c_str());

@@ -15,6 +15,7 @@
 #include "sherpa-onnx/csrc/online-recognizer.h"
 
 bool stop = false;
+float mic_sample_rate = 16000;
 
 static int32_t RecordCallback(const void *input_buffer,
                               void * /*output_buffer*/,
@@ -24,7 +25,8 @@ static int32_t RecordCallback(const void *input_buffer,
                               void *user_data) {
   auto stream = reinterpret_cast<sherpa_onnx::OnlineStream *>(user_data);
 
-  stream->AcceptWaveform(16000, reinterpret_cast<const float *>(input_buffer),
+  stream->AcceptWaveform(mic_sample_rate,
+                         reinterpret_cast<const float *>(input_buffer),
                          frames_per_buffer);
 
   return stop ? paComplete : paContinue;
@@ -81,14 +83,31 @@ for a list of pre-trained models to download.
   PaDeviceIndex num_devices = Pa_GetDeviceCount();
   fprintf(stderr, "Num devices: %d\n", num_devices);
 
-  PaStreamParameters param;
+  int32_t device_index = Pa_GetDefaultInputDevice();
 
-  param.device = Pa_GetDefaultInputDevice();
-  if (param.device == paNoDevice) {
+  if (device_index == paNoDevice) {
     fprintf(stderr, "No default input device found\n");
+    fprintf(stderr, "If you are using Linux, please switch to \n");
+    fprintf(stderr, " ./bin/sherpa-onnx-alsa \n");
     exit(EXIT_FAILURE);
   }
-  fprintf(stderr, "Use default device: %d\n", param.device);
+
+  const char *pDeviceIndex = std::getenv("SHERPA_ONNX_MIC_DEVICE");
+  if (pDeviceIndex) {
+    fprintf(stderr, "Use specified device: %s\n", pDeviceIndex);
+    device_index = atoi(pDeviceIndex);
+  }
+
+  for (int32_t i = 0; i != num_devices; ++i) {
+    const PaDeviceInfo *info = Pa_GetDeviceInfo(i);
+    fprintf(stderr, " %s %d %s\n", (i == device_index) ? "*" : " ", i,
+            info->name);
+  }
+
+  PaStreamParameters param;
+  param.device = device_index;
+
+  fprintf(stderr, "Use device: %d\n", param.device);
 
   const PaDeviceInfo *info = Pa_GetDeviceInfo(param.device);
   fprintf(stderr, "  Name: %s\n", info->name);
@@ -99,6 +118,11 @@ for a list of pre-trained models to download.
 
   param.suggestedLatency = info->defaultLowInputLatency;
   param.hostApiSpecificStreamInfo = nullptr;
+  const char *pSampleRateStr = std::getenv("SHERPA_ONNX_MIC_SAMPLE_RATE");
+  if (pSampleRateStr) {
+    fprintf(stderr, "Use sample rate %f for mic\n", mic_sample_rate);
+    mic_sample_rate = atof(pSampleRateStr);
+  }
   float sample_rate = 16000;
 
   PaStream *stream;

@@ -47,7 +47,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 
-and if you want to select card 3 and the device 0 on that card, please use:
+and if you want to select card 3 and device 0 on that card, please use:
 
   plughw:3,0
 

@@ -13,6 +13,7 @@
 #include "sherpa-onnx/csrc/circular-buffer.h"
 #include "sherpa-onnx/csrc/microphone.h"
 #include "sherpa-onnx/csrc/offline-recognizer.h"
+#include "sherpa-onnx/csrc/resample.h"
 #include "sherpa-onnx/csrc/voice-activity-detector.h"
 
 bool stop = false;
@@ -115,14 +116,29 @@ to download models for offline ASR.
   PaDeviceIndex num_devices = Pa_GetDeviceCount();
   fprintf(stderr, "Num devices: %d\n", num_devices);
 
-  PaStreamParameters param;
+  int32_t device_index = Pa_GetDefaultInputDevice();
 
-  param.device = Pa_GetDefaultInputDevice();
-  if (param.device == paNoDevice) {
+  if (device_index == paNoDevice) {
     fprintf(stderr, "No default input device found\n");
     exit(EXIT_FAILURE);
   }
-  fprintf(stderr, "Use default device: %d\n", param.device);
+
+  const char *pDeviceIndex = std::getenv("SHERPA_ONNX_MIC_DEVICE");
+  if (pDeviceIndex) {
+    fprintf(stderr, "Use specified device: %s\n", pDeviceIndex);
+    device_index = atoi(pDeviceIndex);
+  }
+
+  for (int32_t i = 0; i != num_devices; ++i) {
+    const PaDeviceInfo *info = Pa_GetDeviceInfo(i);
+    fprintf(stderr, " %s %d %s\n", (i == device_index) ? "*" : " ", i,
+            info->name);
+  }
+
+  PaStreamParameters param;
+  param.device = device_index;
+
+  fprintf(stderr, "Use device: %d\n", param.device);
 
   const PaDeviceInfo *info = Pa_GetDeviceInfo(param.device);
   fprintf(stderr, "  Name: %s\n", info->name);
@@ -133,12 +149,27 @@ to download models for offline ASR.
 
   param.suggestedLatency = info->defaultLowInputLatency;
   param.hostApiSpecificStreamInfo = nullptr;
+  float mic_sample_rate = 16000;
+  const char *pSampleRateStr = std::getenv("SHERPA_ONNX_MIC_SAMPLE_RATE");
+  if (pSampleRateStr) {
+    fprintf(stderr, "Use sample rate %f for mic\n", mic_sample_rate);
+    mic_sample_rate = atof(pSampleRateStr);
+  }
   float sample_rate = 16000;
+  std::unique_ptr<sherpa_onnx::LinearResample> resampler;
+  if (mic_sample_rate != sample_rate) {
+    float min_freq = std::min(mic_sample_rate, sample_rate);
+    float lowpass_cutoff = 0.99 * 0.5 * min_freq;
+
+    int32_t lowpass_filter_width = 6;
+    resampler = std::make_unique<sherpa_onnx::LinearResample>(
+        mic_sample_rate, sample_rate, lowpass_cutoff, lowpass_filter_width);
+  }
 
   PaStream *stream;
   PaError err =
       Pa_OpenStream(&stream, &param, nullptr, /* &outputParameters, */
-                    sample_rate,
+                    mic_sample_rate,
                     0,          // frames per buffer
                     paClipOff,  // we won't output out of range samples
                                 // so don't bother clipping them
@@ -168,6 +199,13 @@ to download models for offline ASR.
       while (buffer.Size() >= window_size) {
         std::vector<float> samples = buffer.Get(buffer.Head(), window_size);
         buffer.Pop(window_size);
+
+        if (resampler) {
+          std::vector<float> tmp;
+          resampler->Resample(samples.data(), samples.size(), true, &tmp);
+          samples = std::move(tmp);
+        }
+
         vad->AcceptWaveform(samples.data(), samples.size());
       }
     }

@@ -12,6 +12,7 @@
 #include "portaudio.h"  // NOLINT
 #include "sherpa-onnx/csrc/circular-buffer.h"
 #include "sherpa-onnx/csrc/microphone.h"
+#include "sherpa-onnx/csrc/resample.h"
 #include "sherpa-onnx/csrc/voice-activity-detector.h"
 #include "sherpa-onnx/csrc/wave-writer.h"
 
@@ -76,14 +77,31 @@ wget https://github.com/snakers4/silero-vad/raw/master/files/silero_vad.onnx
   PaDeviceIndex num_devices = Pa_GetDeviceCount();
   fprintf(stderr, "Num devices: %d\n", num_devices);
 
-  PaStreamParameters param;
+  int32_t device_index = Pa_GetDefaultInputDevice();
 
-  param.device = Pa_GetDefaultInputDevice();
-  if (param.device == paNoDevice) {
+  if (device_index == paNoDevice) {
     fprintf(stderr, "No default input device found\n");
+    fprintf(stderr, "If you are using Linux, please switch to \n");
+    fprintf(stderr, " ./bin/sherpa-onnx-vad-alsa \n");
     exit(EXIT_FAILURE);
   }
-  fprintf(stderr, "Use default device: %d\n", param.device);
+
+  const char *pDeviceIndex = std::getenv("SHERPA_ONNX_MIC_DEVICE");
+  if (pDeviceIndex) {
+    fprintf(stderr, "Use specified device: %s\n", pDeviceIndex);
+    device_index = atoi(pDeviceIndex);
+  }
+
+  for (int32_t i = 0; i != num_devices; ++i) {
+    const PaDeviceInfo *info = Pa_GetDeviceInfo(i);
+    fprintf(stderr, " %s %d %s\n", (i == device_index) ? "*" : " ", i,
+            info->name);
+  }
+
+  PaStreamParameters param;
+  param.device = device_index;
+
+  fprintf(stderr, "Use device: %d\n", param.device);
 
   const PaDeviceInfo *info = Pa_GetDeviceInfo(param.device);
   fprintf(stderr, "  Name: %s\n", info->name);
@@ -94,12 +112,28 @@ wget https://github.com/snakers4/silero-vad/raw/master/files/silero_vad.onnx
 
   param.suggestedLatency = info->defaultLowInputLatency;
   param.hostApiSpecificStreamInfo = nullptr;
+  float mic_sample_rate = 16000;
+  const char *pSampleRateStr = std::getenv("SHERPA_ONNX_MIC_SAMPLE_RATE");
+  if (pSampleRateStr) {
+    fprintf(stderr, "Use sample rate %f for mic\n", mic_sample_rate);
+    mic_sample_rate = atof(pSampleRateStr);
+  }
   float sample_rate = 16000;
 
+  std::unique_ptr<sherpa_onnx::LinearResample> resampler;
+  if (mic_sample_rate != sample_rate) {
+    float min_freq = std::min(mic_sample_rate, sample_rate);
+    float lowpass_cutoff = 0.99 * 0.5 * min_freq;
+
+    int32_t lowpass_filter_width = 6;
+    resampler = std::make_unique<sherpa_onnx::LinearResample>(
+        mic_sample_rate, sample_rate, lowpass_cutoff, lowpass_filter_width);
+  }
+
   PaStream *stream;
   PaError err =
       Pa_OpenStream(&stream, &param, nullptr, /* &outputParameters, */
-                    sample_rate,
+                    mic_sample_rate,
                     0,          // frames per buffer
                     paClipOff,  // we won't output out of range samples
                                 // so don't bother clipping them
@@ -131,6 +165,13 @@ wget https://github.com/snakers4/silero-vad/raw/master/files/silero_vad.onnx
       while (buffer.Size() >= window_size) {
         std::vector<float> samples = buffer.Get(buffer.Head(), window_size);
         buffer.Pop(window_size);
+
+        if (resampler) {
+          std::vector<float> tmp;
+          resampler->Resample(samples.data(), samples.size(), true, &tmp);
+          samples = std::move(tmp);
+        }
+
         vad->AcceptWaveform(samples.data(), samples.size());
 
         if (vad->IsSpeechDetected() && !printed) {
@@ -149,7 +190,7 @@ wget https://github.com/snakers4/silero-vad/raw/master/files/silero_vad.onnx
           char filename[128];
           snprintf(filename, sizeof(filename), "seg-%d-%.3fs.wav", k, duration);
           k += 1;
-          sherpa_onnx::WriteWave(filename, 16000, segment.samples.data(),
+          sherpa_onnx::WriteWave(filename, sample_rate, segment.samples.data(),
                                  segment.samples.size());
           fprintf(stderr, "Saved to %s\n", filename);
           fprintf(stderr, "----------\n");