moments

geometryfunctionOpenCV 5.0.0

import { moments } from '@banou/opencv-wasm'

Use after await initOpenCV(). See the initialization and named imports guide.

Explore visually: Image and contour moments →

Summarize how a region’s mass is distributed over its coordinates.

VISUAL WALKTHROUGHShape

REFERENCE INPUTShape with a concavity

The inward notch distinguishes the original boundary from its convex hull.

→

RESULTCentroid and principal spread

The centroid and axes illustrate geometric descriptors. They summarize the region rather than reproducing every boundary sample.

Illustrative example. The stages explain the method; they are not a live OpenCV execution.

Calculates all of the moments up to the third order of a polygon or rasterized shape.

The function computes moments, up to the 3rd order, of a vector shape or a rasterized shape. The results are returned in the structure cv::Moments.

Note: Only applicable to contour moments calculations from Python bindings: Note that the numpy type for the input array should be either np.int32 or np.float32.

Note: For contour-based moments, the zeroth-order moment m00 represents the contour area.

If the input contour is degenerate (for example, a single point or all points are collinear), the area is zero and therefore m00 == 0.

In this case, the centroid coordinates (m10/m00, m01/m00) are undefined and must be handled explicitly by the caller.

A common workaround is to compute the center using cv::boundingRect() or by averaging the input points.

See: contourArea, arcLength

moments(array: Mat, binaryImage: boolean): Moments;

2 available overloads

moments(array: Mat): Moments;

moments(array: Mat, binaryImage: boolean): Moments;

array

Single channel raster image (CV_8U, CV_16U, CV_16S, CV_32F, CV_64F) or an array ( 1 \times N or N \times 1 ) of 2D points (Point or Point2f).

binaryImage

If it is true, all non-zero image pixels are treated as 1's. The parameter is used for images only.

Returns

moments.

Upstream declaration ↗

These signatures describe this package. Upstream documentation can mention optional backends that are absent from this build. Check runtime compatibility before choosing a backend or file format.