Circularity

tomni.contour_operations.circularity(contour: numpy.ndarray) → float[source]

Calculate the circularity of a contour.

The circularity of a contour is a measure of how closely it resembles a perfect circle. It is calculated based on the contour’s area and perimeter.

Parameters: contour (np.ndarray) – The contour represented as an OpenCV ndarray.
Returns: The circularity value, where 0 < circularity <= 1.
Return type: float

Example

>>> contour = np.array([[[1, 2]], [[2, 3]], [[3, 2]], [[2, 1]]])
>>> circularity(contour)
0.7853981633974483  # Approximate circularity of a square.

Note

Formula: Circularity = (4 * π * area) / (perimeter^2)
Circularities close to 0 indicate more irregular shapes, while circularities close to 1 suggest shapes that closely resemble a perfect circle.