Add timestamps and tokens for .Net's online models. (#690)

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

@@ -162,15 +162,17 @@ const SherpaOnnxOnlineRecognizerResult *GetOnlineStreamResult(
   memset(r, 0, sizeof(SherpaOnnxOnlineRecognizerResult));
 
   // copy text
-  r->text = new char[text.size() + 1];
-  std::copy(text.begin(), text.end(), const_cast<char *>(r->text));
-  const_cast<char *>(r->text)[text.size()] = 0;
+  char *pText = new char[text.size() + 1];
+  std::copy(text.begin(), text.end(), pText);
+  pText[text.size()] = 0;
+  r->text = pText;
 
   // copy json
   const auto &json = result.AsJsonString();
-  r->json = new char[json.size() + 1];
-  std::copy(json.begin(), json.end(), const_cast<char *>(r->json));
-  const_cast<char *>(r->json)[json.size()] = 0;
+  char *pJson = new char[json.size() + 1];
+  std::copy(json.begin(), json.end(), pJson);
+  pJson[json.size()] = 0;
+  r->json = pJson;
 
   // copy tokens
   auto count = result.tokens.size();
@@ -183,15 +185,12 @@ const SherpaOnnxOnlineRecognizerResult *GetOnlineStreamResult(
 
     r->count = count;
     // Each word ends with nullptr
-    r->tokens = new char[total_length];
-    memset(reinterpret_cast<void *>(const_cast<char *>(r->tokens)), 0,
-           total_length);
+    char *tokens = new char[total_length]{};
     char **tokens_temp = new char *[r->count];
     int32_t pos = 0;
     for (int32_t i = 0; i < r->count; ++i) {
-      tokens_temp[i] = const_cast<char *>(r->tokens) + pos;
-      memcpy(reinterpret_cast<void *>(const_cast<char *>(r->tokens + pos)),
-             result.tokens[i].c_str(), result.tokens[i].size());
+      tokens_temp[i] = tokens + pos;
+      memcpy(tokens + pos, result.tokens[i].c_str(), result.tokens[i].size());
       // +1 to move past the null character
       pos += result.tokens[i].size() + 1;
     }
@@ -205,6 +204,7 @@ const SherpaOnnxOnlineRecognizerResult *GetOnlineStreamResult(
       r->timestamps = nullptr;
     }
 
+    r->tokens = tokens;
   } else {
     r->count = 0;
     r->timestamps = nullptr;
@@ -391,9 +391,10 @@ const SherpaOnnxOfflineRecognizerResult *GetOfflineStreamResult(
   auto r = new SherpaOnnxOfflineRecognizerResult;
   memset(r, 0, sizeof(SherpaOnnxOfflineRecognizerResult));
 
-  r->text = new char[text.size() + 1];
-  std::copy(text.begin(), text.end(), const_cast<char *>(r->text));
-  const_cast<char *>(r->text)[text.size()] = 0;
+  char *pText = new char[text.size() + 1];
+  std::copy(text.begin(), text.end(), pText);
+  pText[text.size()] = 0;
+  r->text = pText;
 
   if (!result.timestamps.empty()) {
     r->timestamps = new float[result.timestamps.size()];
@@ -530,15 +531,17 @@ const SherpaOnnxKeywordResult *GetKeywordResult(
   r->start_time = result.start_time;
 
   // copy keyword
-  r->keyword = new char[keyword.size() + 1];
-  std::copy(keyword.begin(), keyword.end(), const_cast<char *>(r->keyword));
-  const_cast<char *>(r->keyword)[keyword.size()] = 0;
+  char *pKeyword = new char[keyword.size() + 1];
+  std::copy(keyword.begin(), keyword.end(), pKeyword);
+  pKeyword[keyword.size()] = 0;
+  r->keyword = pKeyword;
 
   // copy json
   const auto &json = result.AsJsonString();
-  r->json = new char[json.size() + 1];
-  std::copy(json.begin(), json.end(), const_cast<char *>(r->json));
-  const_cast<char *>(r->json)[json.size()] = 0;
+  char *pJson = new char[json.size() + 1];
+  std::copy(json.begin(), json.end(), pJson);
+  pJson[json.size()] = 0;
+  r->json = pJson;
 
   // copy tokens
   auto count = result.tokens.size();
@@ -551,18 +554,16 @@ const SherpaOnnxKeywordResult *GetKeywordResult(
 
     r->count = count;
     // Each word ends with nullptr
-    r->tokens = new char[total_length];
-    memset(reinterpret_cast<void *>(const_cast<char *>(r->tokens)), 0,
-           total_length);
+    char *pTokens = new char[total_length]{};
     char **tokens_temp = new char *[r->count];
     int32_t pos = 0;
     for (int32_t i = 0; i < r->count; ++i) {
-      tokens_temp[i] = const_cast<char *>(r->tokens) + pos;
-      memcpy(reinterpret_cast<void *>(const_cast<char *>(r->tokens + pos)),
-             result.tokens[i].c_str(), result.tokens[i].size());
+      tokens_temp[i] = pTokens + pos;
+      memcpy(pTokens + pos, result.tokens[i].c_str(), result.tokens[i].size());
       // +1 to move past the null character
       pos += result.tokens[i].size() + 1;
     }
+    r->tokens = pTokens;
     r->tokens_arr = tokens_temp;
 
     if (!result.timestamps.empty()) {

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

@@ -145,6 +145,10 @@ SHERPA_ONNX_API typedef struct SherpaOnnxOnlineRecognizerResult {
   const char *const *tokens_arr;
 
   // Pointer to continuous memory which holds timestamps
+  //
+  // Caution: If timestamp information is not available, this pointer is NULL.
+  // Please check whether it is NULL before you access it; otherwise, you would
+  // get segmentation fault.
   float *timestamps;
 
   // The number of tokens/timestamps in above pointer

sherpa-onnx/csrc/online-zipformer2-transducer-model.h

@@ -105,7 +105,7 @@ class OnlineZipformer2TransducerModel : public OnlineTransducerModel {
 
   int32_t context_size_ = 0;
   int32_t vocab_size_ = 0;
-  int32_t feature_dim_ = 0;
+  int32_t feature_dim_ = 80;
 };
 
 }  // namespace sherpa_onnx