partimorph 0.1.4

Particle shape analysis and visualization library.

PartiMorph

2D binary particle shape analysis library. Computes four morphological metrics from a binary mask:

• Wadell roundness — corner curvature-based roundness
• ISO circularity — perimeter-area ratio
• Riley sphericity — inscribed/enclosing circle ratio
• Aspect ratio — fitted ellipse major/minor axis ratio

All values are dimensionless ratios (0–1, except aspect ratio which is >= 1).

Installation

Python 3.12+

pip install partimorph

Quick Start

import partimorph as pm

mask = pm.utils.create_circle_mask((256, 256), (128, 128), 60)
results = pm.analyze_mask(mask)

print(results["roundness"]["val"])
print(results["circularity"]["val"])
print(results["sphericity"]["val"])
print(results["aspect_ratio"]["val"])

Visualize the results:

pm.utils.plot_analysis_results(mask, results)

API

pm.analyze_mask(
    mask,
    use_aspect_ratio=True,
    use_roundness=True,
    use_circularity=True,
    use_sphericity=True,
    roundness_params=None,
    eps=0.001,
    target_dim=384,
)

Parameter	Description
mask	2D numpy.ndarray with bool or {0, 1} values
use_*	Toggle individual metrics on/off
roundness_params	Optional dict to override Wadell roundness parameters
eps	Tolerance for geometric computations
target_dim	Large masks are downscaled to this size for speed

Returns an AnalysisResult dict. Keys are only present for enabled metrics (use_*=True).

Result Shape

{
  "roundness": {"val": float} | None,
  "circularity": {"val": float} | None,
  "sphericity": {
    "val": float,
    "inscribed": {"x": float, "y": float, "r": float},
    "enclosing": {"x": float, "y": float, "r": float},
  } | None,
  "aspect_ratio": {
    "val": float,
    "ellipse": {
      "major": float, "minor": float,
      "x": float, "y": float, "angle": float,
      "w": float, "h": float, "bbox": list[list[float]],
    },
  } | None,
}

Input Rules

• mask must be a 2D numpy.ndarray
• Allowed values: bool or {0, 1}
• Empty mask returns None

Utilities

• pm.utils.create_particle_mask(...) — synthetic mask generator with Fourier roughness control
• pm.utils.plot_analysis_results(mask, results) — overlay visualization of all computed metrics

License

MIT