Add C and C++ API for Moonshine models (#1476)

c-api-examples/vad-whisper-c-api.c

@@ -0,0 +1,169 @@
+// c-api-examples/vad-whisper-c-api.c
+//
+// Copyright (c)  2024  Xiaomi Corporation
+
+//
+// This file demonstrates how to use VAD + Whisper tiny.en with
+// sherpa-onnx's C API.
+//
+// clang-format off
+//
+// wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/silero_vad.onnx
+// wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/Obama.wav
+//
+// wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-whisper-tiny.en.tar.bz2
+// tar xvf sherpa-onnx-whisper-tiny.en.tar.bz2
+// rm sherpa-onnx-whisper-tiny.en.tar.bz2
+//
+// clang-format on
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "sherpa-onnx/c-api/c-api.h"
+
+int32_t main() {
+  const char *wav_filename = "./Obama.wav";
+  const char *vad_filename = "./silero_vad.onnx";
+
+  const char *encoder = "sherpa-onnx-whisper-tiny.en/tiny.en-encoder.int8.onnx";
+  const char *decoder = "sherpa-onnx-whisper-tiny.en/tiny.en-decoder.int8.onnx";
+  const char *tokens = "sherpa-onnx-whisper-tiny.en/tiny.en-tokens.txt";
+
+  const SherpaOnnxWave *wave = SherpaOnnxReadWave(wav_filename);
+  if (wave == NULL) {
+    fprintf(stderr, "Failed to read %s\n", wav_filename);
+    return -1;
+  }
+
+  if (wave->sample_rate != 16000) {
+    fprintf(stderr, "Expect the sample rate to be 16000. Given: %d\n",
+            wave->sample_rate);
+    SherpaOnnxFreeWave(wave);
+    return -1;
+  }
+
+  // Offline model config
+  SherpaOnnxOfflineModelConfig offline_model_config;
+  memset(&offline_model_config, 0, sizeof(offline_model_config));
+  offline_model_config.debug = 0;
+  offline_model_config.num_threads = 1;
+  offline_model_config.provider = "cpu";
+  offline_model_config.tokens = tokens;
+  offline_model_config.whisper.encoder = encoder;
+  offline_model_config.whisper.decoder = decoder;
+  offline_model_config.whisper.language = "en";
+  offline_model_config.whisper.tail_paddings = 0;
+  offline_model_config.whisper.task = "transcribe";
+
+  // Recognizer config
+  SherpaOnnxOfflineRecognizerConfig recognizer_config;
+  memset(&recognizer_config, 0, sizeof(recognizer_config));
+  recognizer_config.decoding_method = "greedy_search";
+  recognizer_config.model_config = offline_model_config;
+
+  const SherpaOnnxOfflineRecognizer *recognizer =
+      SherpaOnnxCreateOfflineRecognizer(&recognizer_config);
+
+  if (recognizer == NULL) {
+    fprintf(stderr, "Please check your recognizer config!\n");
+    SherpaOnnxFreeWave(wave);
+    return -1;
+  }
+
+  SherpaOnnxVadModelConfig vadConfig;
+  memset(&vadConfig, 0, sizeof(vadConfig));
+  vadConfig.silero_vad.model = vad_filename;
+  vadConfig.silero_vad.threshold = 0.5;
+  vadConfig.silero_vad.min_silence_duration = 0.5;
+  vadConfig.silero_vad.min_speech_duration = 0.5;
+  vadConfig.silero_vad.max_speech_duration = 10;
+  vadConfig.silero_vad.window_size = 512;
+  vadConfig.sample_rate = 16000;
+  vadConfig.num_threads = 1;
+  vadConfig.debug = 1;
+
+  SherpaOnnxVoiceActivityDetector *vad =
+      SherpaOnnxCreateVoiceActivityDetector(&vadConfig, 30);
+
+  if (vad == NULL) {
+    fprintf(stderr, "Please check your recognizer config!\n");
+    SherpaOnnxFreeWave(wave);
+    SherpaOnnxDestroyOfflineRecognizer(recognizer);
+    return -1;
+  }
+
+  int32_t window_size = vadConfig.silero_vad.window_size;
+  int32_t i = 0;
+
+  while (i + window_size < wave->num_samples) {
+    SherpaOnnxVoiceActivityDetectorAcceptWaveform(vad, wave->samples + i,
+                                                  window_size);
+    i += window_size;
+
+    while (!SherpaOnnxVoiceActivityDetectorEmpty(vad)) {
+      const SherpaOnnxSpeechSegment *segment =
+          SherpaOnnxVoiceActivityDetectorFront(vad);
+
+      const SherpaOnnxOfflineStream *stream =
+          SherpaOnnxCreateOfflineStream(recognizer);
+
+      SherpaOnnxAcceptWaveformOffline(stream, wave->sample_rate,
+                                      segment->samples, segment->n);
+
+      SherpaOnnxDecodeOfflineStream(recognizer, stream);
+
+      const SherpaOnnxOfflineRecognizerResult *result =
+          SherpaOnnxGetOfflineStreamResult(stream);
+
+      float start = segment->start / 16000.0f;
+      float duration = segment->n / 16000.0f;
+      float stop = start + duration;
+
+      fprintf(stderr, "%.3f -- %.3f: %s\n", start, stop, result->text);
+
+      SherpaOnnxDestroyOfflineRecognizerResult(result);
+      SherpaOnnxDestroyOfflineStream(stream);
+
+      SherpaOnnxDestroySpeechSegment(segment);
+      SherpaOnnxVoiceActivityDetectorPop(vad);
+    }
+  }
+
+  SherpaOnnxVoiceActivityDetectorFlush(vad);
+
+  while (!SherpaOnnxVoiceActivityDetectorEmpty(vad)) {
+    const SherpaOnnxSpeechSegment *segment =
+        SherpaOnnxVoiceActivityDetectorFront(vad);
+
+    const SherpaOnnxOfflineStream *stream =
+        SherpaOnnxCreateOfflineStream(recognizer);
+
+    SherpaOnnxAcceptWaveformOffline(stream, wave->sample_rate, segment->samples,
+                                    segment->n);
+
+    SherpaOnnxDecodeOfflineStream(recognizer, stream);
+
+    const SherpaOnnxOfflineRecognizerResult *result =
+        SherpaOnnxGetOfflineStreamResult(stream);
+
+    float start = segment->start / 16000.0f;
+    float duration = segment->n / 16000.0f;
+    float stop = start + duration;
+
+    fprintf(stderr, "%.3f -- %.3f: %s\n", start, stop, result->text);
+
+    SherpaOnnxDestroyOfflineRecognizerResult(result);
+    SherpaOnnxDestroyOfflineStream(stream);
+
+    SherpaOnnxDestroySpeechSegment(segment);
+    SherpaOnnxVoiceActivityDetectorPop(vad);
+  }
+
+  SherpaOnnxDestroyOfflineRecognizer(recognizer);
+  SherpaOnnxDestroyVoiceActivityDetector(vad);
+  SherpaOnnxFreeWave(wave);
+
+  return 0;
+}