2.1.2.1.6. sf_tools.image.stats module

IMAGE STATISTICS ROUTINES

This module contains methods for the statistical analysis of images.

Author:Samuel Farrens <samuel.farrens@gmail.com> Version:1.1 Date:20/10/2017

class sf_tools.image.stats.SAT(data)

Summed Area Table

This class produces a Summed Area Table (SAT) for fast and efficient statistics on image patches.

Parameters:data (np.ndarray) – Input 2D data array

Notes

Also know as Itegral Image (i in the class features).

Todo

Add equations and citations

get_area(data, corners)

Get area

This method calculates the area of a patch.

Parameters:

• data (np.ndarray) – Input 2D data array
• corners (tuple) – Positions of upper left and bottom right corners.

Returns:

Return type:

float area

get_npx(corners)

Get number of pixels

This method calculates the number of pixels in a patch.

Parameters:corners (tuple) – Positions of upper left and bottom right corners. Returns: Return type:int number of pixels

get_var()

Get variance

This method calculates the variance and standard deviation of a patch.

set_patch(corners)

Set patch

This method sets the corner positions of a single patch.

Parameters:corners (tuple) – Positions of upper left and bottom right corners.

set_patches(corners)

Set patches

This method sets the corner positions for multiple patches.

Parameters:corners (list) – List of the positions of upper left and bottom right corners.