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BFMatcher

Features and matchingclassOpenCV 5.0.0
import { BFMatcher } from '@banou/opencv-wasm'

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

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

Brute-force descriptor matcher.

For each descriptor in the first set, this matcher finds the closest descriptor in the second set by trying each one. This descriptor matcher supports masking permissible matches of descriptor sets.

Constructors and members

static new

Brute-force matcher constructor (obsolete). Please use BFMatcher.create()

new(normType: number, crossCheck: boolean): BFMatcher;
3 available overloads
new(): BFMatcher;
new(normType: number): BFMatcher;
new(normType: number, crossCheck: boolean): BFMatcher;
normType

norm type argument (number).

crossCheck

cross check argument (boolean).

Returns

The BFMatcher result.

static create

Brute-force matcher create method.

create(normType: number, crossCheck: boolean): BFMatcher | null;
3 available overloads
create(): BFMatcher | null;
create(normType: number): BFMatcher | null;
create(normType: number, crossCheck: boolean): BFMatcher | null;
normType

One of NORM_L1, NORM_L2, NORM_HAMMING, NORM_HAMMING2. L1 and L2 norms are preferable choices for SIFT and SURF descriptors, NORM_HAMMING should be used with ORB, BRISK and BRIEF, NORM_HAMMING2 should be used with ORB when WTA_K==3 or 4 (see ORB::ORB constructor description).

crossCheck

If it is false, this is will be default BFMatcher behaviour when it finds the k nearest neighbors for each query descriptor. If crossCheck==true, then the knnMatch() method with k=1 will only return pairs (i,j) such that for i-th query descriptor the j-th descriptor in the matcher's collection is the nearest and vice versa, i.e. the BFMatcher will only return consistent pairs. Such technique usually produces best results with minimal number of outliers when there are enough matches. This is alternative to the ratio test, used by D. Lowe in SIFT paper.

Returns

The BFMatcher | null result.

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.