Creates distorted images. More...

#include <Distorter.h>

Public Member Functions
	Distorter (double sigma=5.0, double alpha=36.0/255.0, double beta=15.0, double gammaX=15.0, double gammaY=15.0)

void	createDistortionMap (int rows, int cols)

void	applyDistortions (Eigen::MatrixXd &instances, int rows, int cols)

void	applyDistortion (Eigen::VectorXd &instance, int rows, int cols)

Public Attributes
double	sigma
	elastic distortion More...

double	alpha
	elastic scaling More...

double	beta
	maximal absolute rotation More...

double	gammaX
	maximal horizontal scaling (percent) More...

double	gammaY
	maximal vertical scaling (percent) More...

int	gaussianKernelSize
	has to be odd More...

Eigen::MatrixXd	gaussianKernel

Eigen::MatrixXd	distortionH

Eigen::MatrixXd	distortionV

Detailed Description

Creates distorted images.

Available distortions are:

elastic distortions (emulation of uncontrolled oscillations of the hand muscles)
rotation
horizontal and vertical scaling

To apply elastic distortions, the original image is distorted with random displacements and then convolved with a Gaussian kernel of width $\sigma \in [ 5, 6]$ . Then the values are rescaled by the factor $\alpha \in [36/255, 36/255]$ . Afterwards the image will be rotated by $\beta \in [7.5, 15]$ degrees and scaled horizontally by the factor $\gamma_x \in [15, 20]$ and vertically by $\gamma_y \in [15, 20]$ .