ximgproc_FastLineDetector

Extended image processingclassOpenCV 5.0.0

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

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

ARGUMENTSConstructor or factory

CLASSximgproc_FastLineDetector

RETURN TYPEOwned native handle

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

Native object: release it with using or delete(). Factories can return null; check before calling methods. Inherits Algorithm.

Class implementing the FLD (Fast Line Detector) algorithm described in [Lee14] .

Upstream declaration ↗

Constructors and members

clone

Create another handle to the same native object. This retains the object without copying its pixels or algorithm state; dispose both handles separately.

clone(): this;

Returns

The this result.

detect

example: fld_lines.cpp An example using the FastLineDetector Finds lines in the input image. This is the output of the default parameters of the algorithm on the above shown image.

  ![image](pics/corridor_fld.jpg)

detect(image: Mat, lines: Mat): void;

image: A grayscale (CV_8UC1) input image. If only a roi needs to be selected, use: fld_ptr-\>detect(image(roi), lines, ...); lines += Scalar(roi.x, roi.y, roi.x, roi.y);
lines: Output destination, filled by the native operation. A vector of Vec4f elements specifying the beginning and ending point of a line. Where Vec4f is (x1, y1, x2, y2), point 1 is the start, point 2 - end. Returned lines are directed so that the brighter side is on their left.

Upstream declaration ↗

drawSegments

Draws the line segments on a given image.

drawSegments(image: Mat, lines: Mat, draw_arrow: boolean, linecolor: Scalar, linethickness: number): void;

4 available overloads

drawSegments(image: Mat, lines: Mat): void;

drawSegments(image: Mat, lines: Mat, draw_arrow: boolean): void;

drawSegments(image: Mat, lines: Mat, draw_arrow: boolean, linecolor: Scalar): void;

drawSegments(image: Mat, lines: Mat, draw_arrow: boolean, linecolor: Scalar, linethickness: number): void;

image: Input/output value, modified by the native operation. The image, where the lines will be drawn. Should be bigger or equal to the image, where the lines were found.
lines: A vector of the lines that needed to be drawn.
draw_arrow: If true, arrow heads will be drawn.
linecolor: Line color.
linethickness: Line thickness.

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.