ellipse

Image processingfunctionOpenCV 5.0.0

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

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

ARGUMENTSimg, center, axes, angle

FUNCTIONellipse

RETURN TYPEvoid

Call structure. A void return can still write to destination arguments. The parameter descriptions define inputs, outputs and ownership.

Draws a simple or thick elliptic arc or fills an ellipse sector.

The function cv::ellipse with more parameters draws an ellipse outline, a filled ellipse, an elliptic arc, or a filled ellipse sector. The drawing code uses general parametric form. A piecewise-linear curve is used to approximate the elliptic arc boundary. If you need more control of the ellipse rendering, you can retrieve the curve using #ellipse2Poly and then render it with #polylines or fill it with #fillPoly. If you use the first variant of the function and want to draw the whole ellipse, not an arc, pass startAngle=0 and endAngle=360. If startAngle is greater than endAngle, they are swapped. The figure below explains the meaning of the parameters to draw the blue arc.

Parameters of Elliptic Arc

ellipse(img: Mat, center: Point, axes: Size, angle: number, startAngle: number, endAngle: number, color: Scalar, thickness: number, lineType: number, shift: number): void;

4 available overloads

ellipse(img: Mat, center: Point, axes: Size, angle: number, startAngle: number, endAngle: number, color: Scalar): void;

ellipse(img: Mat, center: Point, axes: Size, angle: number, startAngle: number, endAngle: number, color: Scalar, thickness: number): void;

ellipse(img: Mat, center: Point, axes: Size, angle: number, startAngle: number, endAngle: number, color: Scalar, thickness: number, lineType: number): void;

ellipse(img: Mat, center: Point, axes: Size, angle: number, startAngle: number, endAngle: number, color: Scalar, thickness: number, lineType: number, shift: number): void;

img: Input/output value, modified by the native operation. Image.
center: Center of the ellipse.
axes: Half of the size of the ellipse main axes.
angle: Ellipse rotation angle in degrees.
startAngle: Starting angle of the elliptic arc in degrees.
endAngle: Ending angle of the elliptic arc in degrees.
color: Ellipse color.
thickness: Thickness of the ellipse arc outline, if positive. Otherwise, this indicates that a filled ellipse sector is to be drawn.
lineType: Type of the ellipse boundary. See #LineTypes
shift: Number of fractional bits in the coordinates of the center and values of axes.

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.