pmassbinarization

Performs binarization based on gray level percent.

Synopsis

pmassbinarization ratio [-m mask [im_in|-] [im_out|-]

Description

pmassbinarization sets to 0 every pixel value that is lower to ratio percent of the total gray levels ansd 255 otherwise.

The threshold value is determined as the gray level that splits the image in two class:

ratio% pixels with value < threshold;
100-ratio pixels with value ≥ threshold.

Pixel with value lower or equal to the threshold are set to 0 in the output image, and pixels with value greater than the threshold are set to 255 in the output image.

Parameters

ratio is a real from [0..100] that corresponds to the percentage of pixel in the first cluster.

Inputs

im_in: a grayscale image of bytes (Img2duc, Img3duc).

Outputs

im_out: an image of type char (Img2duc, Img3duc).

Result

Returns the threshold value.

Examples

Discards the background and keeps the tangram pieces from the tangram.pan image:

   pmassbinarization 86 tangram.pan out.pan

C++ prototype

Errc PMassBinarization( const Img2duc &im_in, Img2duc &im_out, Float ratio );

Version française

Binarisation d'une image basé sur le pourcentage de niveaux de gris.

Author: Régis Clouard