HALCON Reference Manual 10.0.2

info_smoothT_info_smoothinfo_smoothInfoSmoothInfoSmooth (Operator)

Name

info_smoothT_info_smoothinfo_smoothInfoSmoothInfoSmooth — Information on smoothing filter smooth_imagesmooth_imagesmooth_imageSmoothImageSmoothImage.

Signature

info_smooth( : : Filter, Alpha : Size, Coeffs)

The operator info_smoothinfo_smoothinfo_smoothInfoSmoothInfoSmooth returns an estimation of the width of the smoothing filters used in routine smooth_imagesmooth_imagesmooth_imageSmoothImageSmoothImage. For this purpose the underlying continuous impulse answers of FilterFilterFilterFilterfilter are scanned until a filter coefficient is smaller than five percent of the maximum coefficient (at the origin). AlphaAlphaAlphaAlphaalpha is the filter parameter (see smooth_imagesmooth_imagesmooth_imageSmoothImageSmoothImage). Currently four filters are supported (parameter FilterFilterFilterFilterfilter):

            'deriche1', 'deriche2', 'shen' and 'gauss'.

The gauss filter was conventionally implemented with filter masks (the other three are recursive filters). In the case of the gauss filter the filter coefficients (of the one-dimensional impulse answer f(n) with n >= 0) are returned in CoeffsCoeffsCoeffsCoeffscoeffs in addition to the filter size.

Parallelization

Multithreading type: reentrant (runs in parallel with non-exclusive operators).
Multithreading scope: global (may be called from any thread).
Processed without parallelization.

Parameters

FilterFilterFilterFilterfilter (input_control) string → (string)

Name of required filter.

Default value: 'deriche2' "deriche2" "deriche2" "deriche2" "deriche2"

List of values: 'deriche1'"deriche1""deriche1""deriche1""deriche1", 'deriche2'"deriche2""deriche2""deriche2""deriche2", 'shen'"shen""shen""shen""shen", 'gauss'"gauss""gauss""gauss""gauss"

AlphaAlphaAlphaAlphaalpha (input_control) real → (real)

Filter parameter: small values effect strong smoothing (reversed in case of 'gauss').

Default value: 0.5

Suggested values: 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 5.0, 7.0, 10.0

Typical range of values: 0.01 ≤ Alpha Alpha Alpha Alpha alpha ≤ 50.0

Minimum increment: 0.01

Recommended increment: 0.1

Restriction: Alpha > 0.0

SizeSizeSizeSizesize (output_control) integer → (integer)

Width of filter is approx. size x size pixels.

CoeffsCoeffsCoeffsCoeffscoeffs (output_control) integer-array → (integer)

In case of gauss filter: coefficients of the “positive” half of the 1D impulse answer.

Example (HDevelop)

info_smooth('deriche2',0.5,Size,Coeffs)
smooth_image(Input,Smooth,'deriche2',7)

Example (C)

info_smooth('deriche2',0.5,Size,Coeffs);
smooth_image(Input,&Smooth,'deriche2',7);

Example (HDevelop)

info_smooth('deriche2',0.5,Size,Coeffs)
smooth_image(Input,Smooth,'deriche2',7)

Example (HDevelop)

info_smooth('deriche2',0.5,Size,Coeffs)
smooth_image(Input,Smooth,'deriche2',7)

Example (HDevelop)

info_smooth('deriche2',0.5,Size,Coeffs)
smooth_image(Input,Smooth,'deriche2',7)

Result

If the parameter values are correct the operator info_smoothinfo_smoothinfo_smoothInfoSmoothInfoSmooth returns the value 2 (H_MSG_TRUE). Otherwise an exception is raised.