{
  "model_type": "phpwind-captcha-ocr",
  "task": "captcha-ocr",
  "framework": "pytorch",
  "format": "onnx",
  "onnx_opsets": [18],
  "num_params": 988786,
  "input": {
    "name": "input",
    "shape": ["batch", 3, 64, 160],
    "dtype": "float32",
    "range": [0.0, 1.0]
  },
  "output": {
    "name": "logits",
    "shape": ["batch", 4, 10],
    "dtype": "float32"
  },
  "task_spec": {
    "num_digits": 4,
    "charset": "0123456789",
    "decode": "argmax over last dim per position"
  },
  "preprocessing": {
    "mode": "RGB",
    "resize": [160, 64],
    "resample": "BILINEAR",
    "denoise": false,
    "normalize": "divide by 255"
  },
  "training": {
    "dataset_size": 997,
    "label_source": "human",
    "epochs": 500,
    "best_epoch": 50,
    "optimizer": "Adam",
    "learning_rate": 0.001,
    "lr_scheduler": "ReduceLROnPlateau(patience=10, factor=0.5)",
    "loss": "sum of 4 CrossEntropy",
    "augmentation": "rotation ±6 deg, scale 0.92-1.08, translate ±3px, no gaussian noise",
    "val_split": 0.08
  },
  "metrics": {
    "val_accuracy": 0.8861
  }
}