models/model_config.json

{
  "input_shape": [
    50,
    50,
    1
  ],
  "pixel_convention": "digit stroke = 0, background = 1 (inverted binary, see clean_and_resize_optimized)",
  "normalization": "binary 0/1 via Otsu threshold + bitwise_not, then /255",
  "num_classes": 10,
  "class_mapping": "index == digit value (0-9)"
}