add blank_penalty for offline transducer (#542)

2024-01-25 15:00:09 +08:00
parent a9e7747736
commit 3bb3849ec5
13 changed files with 97 additions and 14 deletions
--- a/sherpa-onnx/csrc/offline-transducer-modified-beam-search-decoder.cc
+++ b/sherpa-onnx/csrc/offline-transducer-modified-beam-search-decoder.cc
@@ -97,6 +97,10 @@ OfflineTransducerModifiedBeamSearchDecoder::Decode(
        model_->RunJoiner(std::move(cur_encoder_out), View(&decoder_out));

    float *p_logit = logit.GetTensorMutableData<float>();
+    if (blank_penalty_ > 0.0) {
+      // assuming blank id is 0
+      SubtractBlank(p_logit, vocab_size, num_hyps, 0, blank_penalty_);
+    }
    LogSoftmax(p_logit, vocab_size, num_hyps);

    // now p_logit contains log_softmax output, we rename it to p_logprob