alphamat_infoFlow

alphamatfunctionOpenCV 5.0.0

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

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

Explore visually: Alpha matting →

Estimate fractional foreground coverage using an image and a trimap of known foreground, background and unknown pixels.

VISUAL WALKTHROUGHSegmentation

REFERENCE INPUTForeground / unknown / background

White is known foreground, black is background, and grey is the unknown band.

→

RESULTComposite with a new background

Fractional alpha mixes foreground and background instead of producing a hard binary cut.

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

Compute alpha matte of an object in an image

alphamat_infoFlow(image: Mat, tmap: Mat, result: Mat): void;

image

Input RGB image

tmap

Input greyscale trimap image

result

Output destination, filled by the native operation. Output alpha matte image

The function infoFlow performs alpha matting on a RGB image using a greyscale trimap image, and outputs a greyscale alpha matte image. The output alpha matte can be used to softly extract the foreground object from a background image. Examples can be found in the samples directory.

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.