{
  "model": {
    "name": "FormantNet",
    "source": "expdir/mvt33_f6z1sTpF10/weights.sigmoid195-20.143 (TF checkpoint)",
    "architecture": "LSTM(257,512,return_sequences=True) -> Dense(20,sigmoid)",
    "input": {
      "name": "input",
      "shape": ["batch", "time", 257],
      "dtype": "float32",
      "note": "normalized log-spectral envelope, 257 bins (32ms/16kHz window)"
    },
    "output": {
      "name": "dense",
      "shape": ["batch", "time", 20],
      "dtype": "float32",
      "note": "raw sigmoid [0,1]; rescale with FN_model.get_rescale_fn() to get Hz/BW/dB"
    },
    "opset": 15,
    "total_params": 1587220,
    "framework_origin": "tensorflow-macos 2.13 / keras 2.13"
  },
  "variants": {
    "fp32": {
      "file": "formantnet.onnx",
      "size_mb": 6.361,
      "max_abs_diff": 0.0,
      "mean_abs_diff": 0.0,
      "max_rel_diff": 0.0,
      "threshold_abs": 0.0001,
      "pass": true
    },
    "fp16": {
      "file": "formantnet_fp16.onnx",
      "size_mb": 3.184,
      "max_abs_diff": 4.09e-04,
      "mean_abs_diff": 2.49e-05,
      "max_rel_diff": 4.52e-03,
      "threshold_abs": 0.005,
      "pass": true
    },
    "int8": {
      "file": "formantnet_int8.onnx",
      "size_mb": 1.608,
      "max_abs_diff": 9.15e-02,
      "mean_abs_diff": 8.71e-03,
      "max_rel_diff": 0.737,
      "threshold_abs": 0.15,
      "pass": true,
      "note": "max_rel_diff high due to near-zero sigmoid outputs; abs_diff within threshold (same pattern as DeepFormants-onnx int8)"
    }
  },
  "post_processing_outside_onnx": [
    "FFT / spectral envelope extraction (FN_data.py)",
    "Input normalization by training-set mean/std (Normfile)",
    "Output rescaling to Hz/BW/dB (FN_model.get_rescale_fn)",
    "Formant sorting by mean frequency",
    "Binomial smoothing (BIN_SMOOTH_PASSES=10)"
  ],
  "conversion_script": "convert_to_onnx.py",
  "quantization_script": "quantize_onnx.py",
  "validation_script": "validate_onnx.py"
}