OpenVoiceOS/g2p-mbyt5-12l-ipa-childes-espeak-onnx

this model should be usable as a drop-in replacement for espeak

onnx version of fdemelo/g2p-mbyt5-12l-ipa-childes-espeak

inference example

from transformers import AutoTokenizer
import onnxruntime
import numpy as np


def infer_onnx(text: str, lang: str, onnx_model_path: str = "byt5_g2p_model.onnx"):
    """
    Exports the ByT5 model to ONNX format and then performs inference using ONNX Runtime.

    Args:
        text (str): The input text to convert to phonemes.
        lang (str): The language tag (e.g., "en").
        onnx_model_path (str): The path to save/load the ONNX model.
    """
    model_name = 'fdemelo/g2p-multilingual-byt5-tiny-8l-ipa-childes'
    tokenizer = AutoTokenizer.from_pretrained(model_name)

    # --- Step 2: Perform Inference with ONNX Runtime ---
    print("\n--- Performing inference with ONNX Runtime ---")

    # Create an ONNX Runtime session
    try:
        session = onnxruntime.InferenceSession(onnx_model_path, providers=['CPUExecutionProvider'])
    except Exception as e:
        print(f"Error loading ONNX model: {e}")
        return

    # Get input and output names from the ONNX model
    onnx_input_names = [inp.name for inp in session.get_inputs()]
    onnx_output_names = [out.name for out in session.get_outputs()]

    # Prepare actual input for ONNX inference
    input_text_for_onnx = f"<{lang}>: {text}"
    inputs_for_onnx = tokenizer([input_text_for_onnx], return_tensors="pt", add_special_tokens=False)

    input_ids_np = inputs_for_onnx["input_ids"].cpu().numpy()
    attention_mask_np = inputs_for_onnx["attention_mask"].cpu().numpy()

    # Manual greedy decoding loop for ONNX Runtime
    # This simulates the 'generate' method's greedy decoding.
    generated_ids = []
    # T5 models typically use pad_token_id as the initial token for generation
    # or a specific decoder_start_token_id.
    # For T5, the decoder_start_token_id is usually the pad_token_id.
    current_decoder_input_id = tokenizer.pad_token_id if tokenizer.pad_token_id is not None else 0

    # Ensure it's a batch of 1
    decoder_input_ids_np = np.array([[current_decoder_input_id]])

    max_length = 512  # Same as in the original predict_byt5

    # Store encoder outputs if needed for cross-attention in decoder (T5 does this)
    # When exporting the full T5 model's forward pass, the encoder_hidden_states
    # are implicitly handled within the graph. We just need to feed the decoder_input_ids.

    for _ in range(max_length):
        # Prepare inputs for the current step
        onnx_inputs = {
            "input_ids": input_ids_np,
            "attention_mask": attention_mask_np,
            "decoder_input_ids": decoder_input_ids_np
        }

        # Run inference
        outputs = session.run(onnx_output_names, onnx_inputs)
        logits = outputs[0]  # Get the logits

        # Get the logits for the last token in the sequence
        next_token_logits = logits[0, -1, :]  # Batch 0, last token, all vocab logits

        # Greedy decoding: pick the token with the highest logit
        next_token_id = np.argmax(next_token_logits)
        generated_ids.append(next_token_id)

        # Check for end-of-sequence token
        if next_token_id == tokenizer.eos_token_id:
            break

        # Update decoder input for the next step
        # Append the new token to the decoder input sequence
        decoder_input_ids_np = np.concatenate((decoder_input_ids_np, np.array([[next_token_id]])), axis=1)

    # Decode the generated ONNX phoneme IDs
    onnx_phones = tokenizer.batch_decode([generated_ids], skip_special_tokens=True)
    print(f"ONNX Runtime Inference: {onnx_phones}")
    return onnx_phones
``