Lourdle/CosyVoice2-0.5B_ONNX

CosyVoice2 ONNX Models (flow & hift)

This repository provides ONNX-format models for selected modules of CosyVoice2, including:

• flow_fp32.onnx (full precision, flow module)
• flow_fp16.onnx (half precision, flow module)
• hift.onnx (full precision, hift module)
• flow_hift_combined_fp32.onnx (combined flow_fp32 and hift model)
• flow_hift_combined_fp16.onnx (combined flow_fp16 and hift model)

Update 2025-11-09: Fixed the NaN issue in the /decoder/estimator submodule of the flow model under half-precision. flow_fp16.onnx has been updated to a fully half-precision flow model. The combined models have also been updated.

For usage instructions, please refer to the GitHub repository.
Other modules of CosyVoice2 can be obtained from the official CosyVoice2.
I have open-sourced the ONNX version of CosyVoice2, including the modified modules and conversion scripts needed for ONNX. If you want to learn how to perform the conversion, please visit CosyVoiceForOnnx.

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Model Inputs and Outputs

flow_fp32.onnx / flow_fp16.onnx

• Inputs:
  • token (int64)
  • prompt_token (int32)
  • prompt_feat (float32 / float16)
  • embedding (float32 / float16)
    • For flow_fp32.onnx, must use float32
    • For flow_fp16.onnx, must use float16
• Outputs:
  • tts_mel (float32)

hift.onnx

• Input:
  • speech_feat (float32)
• Output:
  • generated_speech (float32)

flow_hift_combined_fp32.onnx / flow_hift_combined_fp16.onnx

• Inputs
  • token (int32)
  • prompt_token (int32)
  • prompt_feat (float32 / float16)
  • embedding (float16)
  • speed (float32, scalar, controls speech rate)
    • For flow_hift_combined_fp32.onnx, must use float32
    • For flow_hift_combined_fp16.onnx, must use float16
• Output
  • generated_speech (float32)

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Notes

• All outputs are float32.
• Input precision must strictly match the model requirements.
• Note: in the combined model, token input is int32 (not int64). The speed input is a float32 scalar controlling speech speed.

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Acknowledgments

The original models are from the official CosyVoice2. This repository only provides ONNX format conversion and adaptation.

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