feat: find best embedding matches (#1102)

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

@@ -1256,6 +1256,44 @@ void SherpaOnnxSpeakerEmbeddingManagerFreeSearch(const char *name) {
   delete[] name;
 }
 
+const SherpaOnnxSpeakerEmbeddingManagerBestMatchesResult *
+SherpaOnnxSpeakerEmbeddingManagerGetBestMatches(
+    const SherpaOnnxSpeakerEmbeddingManager *p, const float *v, float threshold,
+    int32_t n) {
+  auto matches = p->impl->GetBestMatches(v, threshold, n);
+
+  if (matches.empty()) {
+    return nullptr;
+  }
+
+  auto resultMatches =
+      new SherpaOnnxSpeakerEmbeddingManagerSpeakerMatch[matches.size()];
+  for (int i = 0; i < matches.size(); ++i) {
+    resultMatches[i].score = matches[i].score;
+
+    char *name = new char[matches[i].name.size() + 1];
+    std::copy(matches[i].name.begin(), matches[i].name.end(), name);
+    name[matches[i].name.size()] = '\0';
+
+    resultMatches[i].name = name;
+  }
+
+  auto *result = new SherpaOnnxSpeakerEmbeddingManagerBestMatchesResult();
+  result->count = matches.size();
+  result->matches = resultMatches;
+
+  return result;
+}
+
+void SherpaOnnxSpeakerEmbeddingManagerFreeBestMatches(
+    const SherpaOnnxSpeakerEmbeddingManagerBestMatchesResult *r) {
+  for (int32_t i = 0; i < r->count; ++i) {
+    delete[] r->matches[i].name;
+  }
+  delete[] r->matches;
+  delete r;
+};
+
 int32_t SherpaOnnxSpeakerEmbeddingManagerVerify(
     const SherpaOnnxSpeakerEmbeddingManager *p, const char *name,
     const float *v, float threshold) {

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

@@ -1109,6 +1109,39 @@ SHERPA_ONNX_API const char *SherpaOnnxSpeakerEmbeddingManagerSearch(
 SHERPA_ONNX_API void SherpaOnnxSpeakerEmbeddingManagerFreeSearch(
     const char *name);
 
+SHERPA_ONNX_API typedef struct SherpaOnnxSpeakerEmbeddingManagerSpeakerMatch {
+  float score;
+  const char *name;
+} SherpaOnnxSpeakerEmbeddingManagerSpeakerMatch;
+
+SHERPA_ONNX_API typedef struct
+    SherpaOnnxSpeakerEmbeddingManagerBestMatchesResult {
+  const SherpaOnnxSpeakerEmbeddingManagerSpeakerMatch *matches;
+  int32_t count;
+} SherpaOnnxSpeakerEmbeddingManagerBestMatchesResult;
+
+// Get the best matching speakers whose embeddings match the given
+// embedding.
+//
+// @param p Pointer to the SherpaOnnxSpeakerEmbeddingManager instance.
+// @param v Pointer to an array containing the embedding vector.
+// @param threshold Minimum similarity score required for a match (between 0 and
+// 1).
+// @param n Number of best matches to retrieve.
+// @return Returns a pointer to
+// SherpaOnnxSpeakerEmbeddingManagerBestMatchesResult
+//         containing the best matches found. Returns NULL if no matches are
+//         found. The caller is responsible for freeing the returned pointer
+//         using SherpaOnnxSpeakerEmbeddingManagerFreeBestMatches() to
+//         avoid memory leaks.
+SHERPA_ONNX_API const SherpaOnnxSpeakerEmbeddingManagerBestMatchesResult *
+SherpaOnnxSpeakerEmbeddingManagerGetBestMatches(
+    const SherpaOnnxSpeakerEmbeddingManager *p, const float *v, float threshold,
+    int32_t n);
+
+SHERPA_ONNX_API void SherpaOnnxSpeakerEmbeddingManagerFreeBestMatches(
+    const SherpaOnnxSpeakerEmbeddingManagerBestMatchesResult *r);
+
 // Check whether the input embedding matches the embedding of the input
 // speaker.
 //