pelongationselection

Selects regions from elongation factor.

Synopsis

pelongationselection relation threshold [-m mask] [rg_in|-] [rg_out|-]

Description

pelongationselection selects regions from their elongation factor. The parameter relation specifies the order relation to the threshold value that is used to select or not a region.

Elongation is the ratio between the length and the width of the bounding box (the length is the longest side and width the shortest side:

elongation = width(bounding box)/length(bounding box).

Parameters

relation is an integer from [-3,3] which specifies the order relation to the threshold value:
- relation = 3: regions with the maximum value.
- relation = 2: regions >= threshold.
- relation = 1: regions > threshold.
- relation = 0: regions = threshold.
- relation = -1: regions < threshold.
- relation = -2: regions <= threshold.
- relation = -3: regions with the minimum value.
threshold is a real value from [0..1] where 1.0 is for a square or a disc.

Inputs

rg_in: a 2D region map.

Outputs

rg_out: a 2D region map.

Result

Returns the number of selected regions.

Examples

Selects the most elongated regions:

   pelongationselection 3 0 rin.pan rout.pan

C++ prototype

Errc PElongationSelection( const Reg2d &rg_in, Reg2d &rg_out, int relation, float threshold );

Version française

Sélection de régions sur leur valeur d'élongation.

Author: Régis Clouard