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optflow_DualTVL1OpticalFlow

optflowclassOpenCV 5.0.0
import { optflow_DualTVL1OpticalFlow } 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 optflow_DenseOpticalFlow.

"Dual TV L1" Optical Flow Algorithm.

The class implements the "Dual TV L1" optical flow algorithm described in [Zach2007] and [Javier2012] . Here are important members of the class that control the algorithm, which you can set after constructing the class instance:

  • member double tau Time step of the numerical scheme.

  • member double lambda Weight parameter for the data term, attachment parameter. This is the most relevant parameter, which determines the smoothness of the output. The smaller this parameter is, the smoother the solutions we obtain. It depends on the range of motions of the images, so its value should be adapted to each image sequence.

  • member double theta Weight parameter for (u - v)^2, tightness parameter. It serves as a link between the attachment and the regularization terms. In theory, it should have a small value in order to maintain both parts in correspondence. The method is stable for a large range of values of this parameter.

  • member int nscales Number of scales used to create the pyramid of images.

  • member int warps Number of warpings per scale. Represents the number of times that I1(x+u0) and grad( I1(x+u0) ) are computed per scale. This is a parameter that assures the stability of the method. It also affects the running time, so it is a compromise between speed and accuracy.

  • member double epsilon Stopping criterion threshold used in the numerical scheme, which is a trade-off between precision and running time. A small value will yield more accurate solutions at the expense of a slower convergence.

  • member int iterations Stopping criterion iterations number used in the numerical scheme.

C. Zach, T. Pock and H. Bischof, "A Duality Based Approach for Realtime TV-L1 Optical Flow". Javier Sanchez, Enric Meinhardt-Llopis and Gabriele Facciolo. "TV-L1 Optical Flow Estimation".

Constructors and members

static create

Creates instance of cv::DualTVL1OpticalFlow

create(tau: number, lambda: number, theta: number, nscales: number, warps: number, epsilon: number, innnerIterations: number, outerIterations: number, scaleStep: number, gamma: number, medianFiltering: number, useInitialFlow: boolean): optflow_DualTVL1OpticalFlow | null;
13 available overloads
create(): optflow_DualTVL1OpticalFlow | null;
create(tau: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number, warps: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number, warps: number, epsilon: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number, warps: number, epsilon: number, innnerIterations: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number, warps: number, epsilon: number, innnerIterations: number, outerIterations: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number, warps: number, epsilon: number, innnerIterations: number, outerIterations: number, scaleStep: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number, warps: number, epsilon: number, innnerIterations: number, outerIterations: number, scaleStep: number, gamma: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number, warps: number, epsilon: number, innnerIterations: number, outerIterations: number, scaleStep: number, gamma: number, medianFiltering: number): optflow_DualTVL1OpticalFlow | null;
create(tau: number, lambda: number, theta: number, nscales: number, warps: number, epsilon: number, innnerIterations: number, outerIterations: number, scaleStep: number, gamma: number, medianFiltering: number, useInitialFlow: boolean): optflow_DualTVL1OpticalFlow | null;
tau

tau argument (number).

lambda

lambda argument (number).

theta

theta argument (number).

nscales

nscales argument (number).

warps

warps argument (number).

epsilon

epsilon argument (number).

innnerIterations

innner iterations argument (number).

outerIterations

outer iterations argument (number).

scaleStep

scale step argument (number).

gamma

gamma argument (number).

medianFiltering

median filtering argument (number).

useInitialFlow

use initial flow argument (boolean).

Returns

The optflow_DualTVL1OpticalFlow | null result.

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.

getTau

Time step of the numerical scheme See: setTau

getTau(): number;
Returns

The number result.

setTau

Time step of the numerical scheme See: setTau See: getTau

setTau(val: number): void;
val

val argument (number).

getLambda

Weight parameter for the data term, attachment parameter See: setLambda

getLambda(): number;
Returns

The number result.

setLambda

Weight parameter for the data term, attachment parameter See: setLambda See: getLambda

setLambda(val: number): void;
val

val argument (number).

getTheta

Weight parameter for (u - v)^2, tightness parameter See: setTheta

getTheta(): number;
Returns

The number result.

setTheta

Weight parameter for (u - v)^2, tightness parameter See: setTheta See: getTheta

setTheta(val: number): void;
val

val argument (number).

getGamma

coefficient for additional illumination variation term See: setGamma

getGamma(): number;
Returns

The number result.

setGamma

coefficient for additional illumination variation term See: setGamma See: getGamma

setGamma(val: number): void;
val

val argument (number).

getScalesNumber

Number of scales used to create the pyramid of images See: setScalesNumber

getScalesNumber(): number;
Returns

The number result.

setScalesNumber

Number of scales used to create the pyramid of images See: setScalesNumber See: getScalesNumber

setScalesNumber(val: number): void;
val

val argument (number).

getWarpingsNumber

Number of warpings per scale See: setWarpingsNumber

getWarpingsNumber(): number;
Returns

The number result.

setWarpingsNumber

Number of warpings per scale See: setWarpingsNumber See: getWarpingsNumber

setWarpingsNumber(val: number): void;
val

val argument (number).

getEpsilon

Stopping criterion threshold used in the numerical scheme, which is a trade-off between precision and running time See: setEpsilon

getEpsilon(): number;
Returns

The number result.

setEpsilon

Stopping criterion threshold used in the numerical scheme, which is a trade-off between precision and running time See: setEpsilon See: getEpsilon

setEpsilon(val: number): void;
val

val argument (number).

getInnerIterations

Inner iterations (between outlier filtering) used in the numerical scheme See: setInnerIterations

getInnerIterations(): number;
Returns

The number result.

setInnerIterations

Inner iterations (between outlier filtering) used in the numerical scheme See: setInnerIterations See: getInnerIterations

setInnerIterations(val: number): void;
val

val argument (number).

getOuterIterations

Outer iterations (number of inner loops) used in the numerical scheme See: setOuterIterations

getOuterIterations(): number;
Returns

The number result.

setOuterIterations

Outer iterations (number of inner loops) used in the numerical scheme See: setOuterIterations See: getOuterIterations

setOuterIterations(val: number): void;
val

val argument (number).

getUseInitialFlow

Use initial flow See: setUseInitialFlow

getUseInitialFlow(): boolean;
Returns

The boolean result.

setUseInitialFlow

Use initial flow See: setUseInitialFlow See: getUseInitialFlow

setUseInitialFlow(val: boolean): void;
val

val argument (boolean).

getScaleStep

Step between scales (<1) See: setScaleStep

getScaleStep(): number;
Returns

The number result.

setScaleStep

Step between scales (<1) See: setScaleStep See: getScaleStep

setScaleStep(val: number): void;
val

val argument (number).

getMedianFiltering

Median filter kernel size (1 = no filter) (3 or 5) See: setMedianFiltering

getMedianFiltering(): number;
Returns

The number result.

setMedianFiltering

Median filter kernel size (1 = no filter) (3 or 5) See: setMedianFiltering See: getMedianFiltering

setMedianFiltering(val: number): void;
val

val argument (number).

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.