CVB.Net 14.1
TeachParameters Struct Reference

Parameters for teaching a Match3D Dnc finder. More...

Properties

double HeightSensitivity [get, set]
 Minimum gradient magnitude to accept a local gradient as a feature in the depth images. More...
 
int DerivativePatchSize [get, set]
 Smoothing area in pixels for gradient and normal calculation. More...
 
int LocalDistributionSize [get, set]
 Size of area in which local features are distributed (in pixels). More...
 
int NumGradientFeatures [get, set]
 Number of gradient features retained in the classifier. More...
 
int NumNormalFeatures [get, set]
 Number of normal vector features retained in the classifier. More...
 
int ICPShrink [get, set]
 ICP-subsample factor. More...
 
double DistanceKernelSize [get, set]
 Factor for Distance transform calculation. More...
 
static TeachParameters Default [get]
 Default TeachParameters object.
 

Detailed Description

Parameters for teaching a Match3D Dnc finder.

Property Documentation

◆ DerivativePatchSize

int DerivativePatchSize
getset

Smoothing area in pixels for gradient and normal calculation.

This value controls the local environment in the depth images of the examples which is used to calculate gradients and normals. Minimum is 3. Larger values effectively result in a smoothing of the depth images. This value should be odd. Typical values are in the range 3..9. Smaller values should be favored, since the example images of the CAD object are flawless and free of noise.

The corresponding value of Search.SearchParameters.DerivativePatchSize of a detection task should be equal, or - in case of sensor noise - bigger. The minimum value is 3.

◆ DistanceKernelSize

double DistanceKernelSize
getset

Factor for Distance transform calculation.

A so called Huber kernel is used for the calculation of a distance transform of an example. To some extend a Huber kernel can possibly enlarge the convergence basin of ICP-operations, relative to the Euclidian distance transform (factor = 1). A recommended value is 2. The minimum value is 1.

◆ HeightSensitivity

double HeightSensitivity
getset

Minimum gradient magnitude to accept a local gradient as a feature in the depth images.

This value specifies a threshold (in millimeters) above which local height changes are observed as characteristic features. A typical value is 1 mm. This value is also used implicitly during later search tasks. The minimum value is 0.0. This value is also used implicitly during later search tasks.

◆ ICPShrink

int ICPShrink
getset

ICP-subsample factor.

To speed up search tasks, a voxel representation of the examples is pre-calculated. The subsample factor determins the amount of data used to perform an ICP-operation.It strongly influences the recognition speed and the amount of memory used. The recommended value is 4. The minimum value is 1, resulting in no subsampling.

◆ LocalDistributionSize

int LocalDistributionSize
getset

Size of area in which local features are distributed (in pixels).

To account for the finite and discrete example positions the local features are somewhat smeared out. This value specifies the local active range of a single feature. A typical value is 8. The minimum value is 0.

◆ NumGradientFeatures

int NumGradientFeatures
getset

Number of gradient features retained in the classifier.

To speed up the calculation of correspondences during a detection task, the possibly dense gradient features from the examples are thinned out to a minimum necessary number. This number strongly depends on the object itself. Typical values are between 100 and 1000. A value of 0 means that all gradient features should be used.

◆ NumNormalFeatures

int NumNormalFeatures
getset

Number of normal vector features retained in the classifier.

To speed up the calculation of correspondences during a detection task, the dense normal features from the examples are thinned out to a minimum necessary number. This number strongly depends on the object itself. Typical values are between 100 and 1000. A value of 0 means that all normal features should be used.