plinearregression

Approximates image to flat background using linear regression.

Synopsis

plinearregression [im_in|-] [im_out|-]

Description

plinearregression converts an image content into a flat background image, using orthogonal linear regressions. This operator removes all sorts of uneven illumination with a gradually change of background color raising or falling from any part of a border to the opposite border. However, it cannot remove circular spotlight.

Inputs

im_in: a 2D image.

Outputs

im_out: a 2D image of the same type as the input image.

Result

Returns SUCCESS or FAILURE.

Examples

Correction the illumination of the tangram image using background subtraction. The background is approximated by linear regression:

   plinearregression tangram.pan a.pan
   psub tangram.pan a.pan b.pan
   pmeanvalue a.pan; mean=`pstatus`
   paddcst $mean b.pan out.pan

More examples

C++ Prototype

Errc PLinearRegression( const Img2duc &im_in, Img2duc &im_out );

Version française

Calcul de l'approximation du fond d'une image en utilisant la regression linéaire.

Author: Régis Clouard