whisper : add mechanism for aborting the whisper_full() computation

examples/main/main.cpp

@@ -607,6 +607,19 @@ int main(int argc, char ** argv) {
  wparams.new_segment_callback_user_data = &user_data;
  }
 
+ // example for abort mechanism
+ // in this example, we do not abort the processing, but we could if the flag is set to true
+ // the callback is called before every encoder run - if it returns false, the processing is aborted
+ {
+ static bool is_aborted = false; // NOTE: this should be atomic to avoid data race
+
+ wparams.encoder_begin_callback = [](struct whisper_context * ctx, void * user_data) {
+ bool is_aborted = *(bool*)user_data;
+ return !is_aborted;
+ };
+ wparams.encoder_begin_callback_user_data = &is_aborted;
+ }
+
  if (whisper_full_parallel(ctx, wparams, pcmf32.data(), pcmf32.size(), params.n_processors) != 0) {
  fprintf(stderr, "%s: failed to process audio\n", argv[0]);
  return 10;

whisper.cpp

@@ -2451,6 +2451,9 @@ struct whisper_full_params whisper_full_default_params(enum whisper_sampling_str
 
  /*.new_segment_callback =*/ nullptr,
  /*.new_segment_callback_user_data =*/ nullptr,
+
+ /*.encoder_begin_callback =*/ nullptr,
+ /*.encoder_begin_callback_user_data =*/ nullptr,
  };
  } break;
  case WHISPER_SAMPLING_BEAM_SEARCH:
@@ -2497,6 +2500,9 @@ struct whisper_full_params whisper_full_default_params(enum whisper_sampling_str
 
  /*.new_segment_callback =*/ nullptr,
  /*.new_segment_callback_user_data =*/ nullptr,
+
+ /*.encoder_begin_callback =*/ nullptr,
+ /*.encoder_begin_callback_user_data =*/ nullptr,
  };
  } break;
  }
@@ -2659,6 +2665,13 @@ int whisper_full(
  break;
  }
 
+ if (params.encoder_begin_callback) {
+ if (params.encoder_begin_callback(ctx, params.encoder_begin_callback_user_data) == false) {
+ fprintf(stderr, "%s: encoder_begin_callback returned false - aborting\n", __func__);
+ break;
+ }
+ }
+
  // encode audio features starting at offset seek
  if (whisper_encode(ctx, seek, params.n_threads) != 0) {
  fprintf(stderr, "%s: failed to encode\n", __func__);

whisper.h

@@ -185,6 +185,14 @@ extern "C" {
  // Use the whisper_full_...() functions to obtain the text segments
  typedef void (*whisper_new_segment_callback)(struct whisper_context * ctx, int n_new, void * user_data);
 
+ // Encoder begin callback
+ // If not NULL, called before the encoder starts
+ // If it returns false, the computation is aborted
+ typedef bool (*whisper_encoder_begin_callback)(struct whisper_context * ctx, void * user_data);
+
+ // Parameters for the whisper_full() function
+ // If you chnage the order or add new parameters, make sure to update the default values in whisper.cpp:
+ // whisper_full_default_params()
  struct whisper_full_params {
  enum whisper_sampling_strategy strategy;
 
@@ -231,6 +239,9 @@ extern "C" {
 
  whisper_new_segment_callback new_segment_callback;
  void * new_segment_callback_user_data;
+
+ whisper_encoder_begin_callback encoder_begin_callback;
+ void * encoder_begin_callback_user_data;
  };
 
  WHISPER_API struct whisper_full_params whisper_full_default_params(enum whisper_sampling_strategy strategy);